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Evan Granite by David Zierler on December 14, 2020,
Niels Bohr Library & Archives, American Institute of Physics,
College Park, MD USA,
For multiple citations, "AIP" is the preferred abbreviation for the location.
In this interview, David Zierler, Oral Historian for AIP, interviews Evan Granite, Research Chemical Engineer at the National Energy Technology Laboratory in the Department of Energy. He explains the value of his adjunct appointment at the University of Pittsburgh and he provides an overall view of the structure and organization of NETL. Granite recounts his childhood in Brooklyn and his early interests in math and science, and he discusses his undergraduate education at Cooper Union where he focused on chemical engineering. Granite describes his interest in energy issues and his decision to pursue a graduate degree at the University of Rochester, where he focused on hydrocarbon catalysis. He explains his initial work at the Pittsburgh lab of NETL studying mercury pollution and coal emissions. Granite discusses his transition from postdoc to federal employee and his long-term focus on the photochemical removal of mercury from simulated flue gases. He describes his subsequent work on carbon dioxide capture, and the importance of this research on global warming mitigation. Granite discusses the science of fracking, and he explains how the instrumentation available at NETL enables him to conduct cutting-edge research experiments. At the end of the interview, Granite explains how technological advances can theoretically get U.S. energy production to a place where fossil fuels can be burned for the next fifty years with minimal increases in carbon emissions.
This is David Zierler, oral historian for the American Institute of Physics. It is December 14th, 2020. I am so happy to be here with Dr. Evan Granite. Evan, thank you so much for joining me today.
Thank you. It’s nice to meet you.
It’s nice to meet you as well. To get started, would you please tell me your title and institutional affiliation?
Sure. I'm a research chemical engineer with the U.S. Department of Energy, specifically with the National Energy Technology Lab, NETL, in Pittsburgh. I've been at NETL for almost twenty-five years, three years as a postdoc and about twenty-one-plus years as a federal employee. My research over the years is focused on the trace and minor elements in coal, for a long time the bad actors, the pollutant elements, mercury, arsenic, selenium, cadmium, antimony, and then more recently, some of the valuable entity trace and minor elements that are in coal, the rare earths, cobalt, lithium, gallium, germanium, vanadium, to recover them not because they're pollutants, but because they actually have some economic value. So that’s in a nutshell. And I primarily do lab-scale experiments, but I try to set the conditions that are realistic and think about what we would have to do if we were to ever implement this at large scale. That if you have realistic conditions, short contact time, realistic temperatures and pressures and flow rates, you could scale successfully from the smallest lab-scale experiment all the way to a full-scale power plant. And we've had success doing that over the years, that as long as you really think about the ultimate application and the mechanism, the underlying mechanism of what the physical process is, you can have great success doing experiments at the smallest of scales, as long as you do it under the most realistic conditions you can have at those small scales.
Evan, do you also have an affiliation at the University of Pittsburgh?
Yes. I'm an adjunct professor at the University of Pittsburgh Department of Chemical and Petroleum Engineering. And I have to get permission to do this, but I happily occasionally teach courses there, over the years. I've taught the graduate chemical kinetics and catalysis course. And the last three years, I've taught the graduate petroleum and natural gas processing course, at the University of Pittsburgh.
In what ways has having that academic connection either with teaching or working with your academic colleagues, or with bringing graduate students to the lab- in what ways is that beneficial to your overall research?
Oh, it’s very beneficial. Originally, I wanted to be a professor. And I still haven't ruled that out (laughter), and I got to satisfy some of my desire to be a professor by being an adjunct at Pitt. But first, over the years- I mentioned that I was a postdoc for three years when I started at NETL, before becoming a full-time researcher there. And over the years, I've mentored many postdoctoral students that have worked in my lab, as well as summer, we have what is called the Mickey Leland Energy Fellowship, which is a summer program where we have typically undergraduates, but sometimes graduate students, they come to our lab for the summer, and they help us with a project. And we try to make it a good learning experience for them. And I always say that that’s the best summer job in the world. They're here for about ten or twelve weeks. They work on a very narrowly defined research project with us, and they prepare a report at the end that they give to management at our headquarters, and they also give a presentation. And if it really works out well, we try to have a publication to go into a journal from this as well. So, if they actually want to go into academia or into graduate school, it’s an outstanding experience. It looks good on their resume. And not only do they learn a lot, but we end up learning as well. Because we have to mentor them. They don’t have a lot of experience. We talk to them every day. We make sure they don’t hurt themselves in the lab. We give them suggestions. And we go through the things that, for us, are commonplace, but for them are new experiences. I know from experience experiments don’t typically work the first time. A lot of times, they don’t work the fifth or tenth or twentieth time. But as long as you learn something along the way, what didn't work, why didn't it work, and try to go in a better, more fruitful direction, you're doing okay, and you try not to get discouraged. So we try to impart that lesson to the students as well. And then I've had many postdocs over the years. They're typically more seasoned. They have their PhD. I try to pick somebody that has at least a rough background. I typically am biased toward chemistry or chemical engineering. And they come into our lab, and they're on one-year contracts. And I always tell them that if things work out, I hope to have them for two or three years. We're not allowed to have them for more than three years. And I always tell them two is the best, because you get a good research experience, we can hopefully publish a few papers, and you can go on to bigger and better things. Which is good for the student. And you know, we're always happy, too. We feel like we mentored the student and can bask in any reflected glory if they go on to bigger and better things. And I've had some students I'm very proud that have gone on to bigger or better things. One of my students, a postdoc, Albert Presto, he’s now a professor at CMU, and he’s very well known. He does atmospheric pollution research at CMU in Pittsburgh, and I'm very proud of him. I've had another student, Erik Rupp, he went to Stanford, and he was at Stanford for about five or six years, and he did very well. He continued work on mercury that he started in my lab around 2008. So yeah, we're always very proud when they go on to bigger and better things. Because first, it’s the right thing to do; we feel like we did a good job. And if they go on and do great things, we get a little bit of the reflected glory. So, I enjoy that very much.
And Evan, just to give a sense of where you are in the overall structure at NETL, both in terms of you and the organizational hierarchy, who reports to you, and who do you report to? And where is your lab in the overall research environment, both physically and hierarchically, at NETL?
I've had a few labs in Pittsburgh. Right now, I have essentially one lab in Pittsburgh right now. It’s in Building 83. And my immediate supervisors are Erik Albenze and Dave Alman in the- it’s called the Research and Innovation Center. It’s really our in-house, on-site research. NETL, I don’t know if you’ve heard this from the previous folks that you've interviewed, is an interesting organization. We're one of the National Labs. There’s approximately, just off the top of my head, roughly eighteen or nineteen national labs scattered across the country. Most of the national labs, they’re all part of the Department of Energy and they're for the U.S. government, but they're private organizations. They're typically run by a university or a defense company, for the Department of Energy. We're a little bit unusual. We're the only national lab that’s run directly by the federal government. And we're also a little bit unusual; most of our employees are on “the other side” – project management. We have two sites in Pittsburgh. Our primary sites are Pittsburgh; Morgantown, West Virginia; and we have a small site in Albany, Oregon. Most of our NETL funding goes out the door to fund external projects. We have a project management side—we call it “the other side” (laughter)- on the other side of our plateau in Pittsburgh—and it’s also in Morgantown—where there are project managers. There’s over one hundred of them, and they manage external projects, and this is projects funded by NETL, by the Department of Energy, and they're typically at universities and power companies and coal companies scattered across the U.S. That’s where most of the NETL budget goes. But a small fraction, on the order of ten percent or so, stays on-site for the in-house research, and that’s the part of the organization that I'm with. We do the research on-site in Pittsburgh, where I am, but also in Albany, Oregon, and Morgantown, West Virginia.
Evan, let’s take it all the way back to the beginning. I’d like to hear a little bit about your childhood and family background. Let’s start with your parents. Tell me a little bit about them and where they're from.
I grew up in Brooklyn, New York, in New York City. I don’t know if you've detected my Brooklyn accent. I've been in Pittsburgh now for almost twenty-five years, and I went to grad school in upstate New York, in Rochester, New York. So, I've been gone from New York City for a long time, but my wife and family say that when I get excited, the Brooklyn accent comes out. So, I grew up in New York City, in Brooklyn, New York, near Coney Island. Which, it’s an interesting place. It’s a nice place to-
Wait a minute, wait a minute- where in Coney Island?
Between Brighton Beach and Coney Island, near Abraham Lincoln High School.
Okay. My dad is from Seagate.
Oh, yeah, I know exactly where that is. That’s the end of Coney Island. Yeah, the end of the boardwalk. Yes, yes. Whenever there’s a coastal storm, they're always worried about flooding in Seagate.
Yep. And are your parents from Brooklyn as well?
Yeah. I mean, my dad grew up in Manhattan near Hell’s Kitchen. My dad’s almost ninety-two years old. My mom passed away a few years ago. She grew up in the Lower East Side in Manhattan, as well.
And did you go to public schools in Brooklyn?
I went to public school, P.S. 100, near Coney Island and Brighton Beach. And then I went to- in Coney Island, near Sea Gate, Mark Twain Junior High School for the Gifted and Talented, which was kind of a strange experiment in the mid and late 1970s. It was a magnet school in Brooklyn in Coney Island. Even though I could walk there, it was about a mile away, and occasionally I did walk when I missed the bus, or the bus broke down but normally I took the bus. But it was a strange experiment, social engineering experiment, because they had math talent, music talent, gym talent (laughter). So sometimes they had some rough characters that they squeezed in on the gym talent, in the same class or homeroom with some of the nerds, or the math talent. I learned how to fight a little bit, because of that (laughter). I was in the math talent. Yes! Sometimes I tell my wife, I kid my wife that I sometimes resent that social engineering experiment from Brooklyn, New York, from over forty years ago. But hopefully it did me some good! And then I went to Lincoln High School for high school. And that was a pretty good experience, but again, that was a strange school. It’s a beautiful school. It’s enormous. It’s bigger than the college I went to. I went to Cooper Union for my bachelor and master’s degree in Manhattan. That’s a tiny, tiny college. Back then and even now I believe, it’s still just three small buildings in the middle of Greenwich Village, with no campus. Abraham Lincoln High School was from about 1929, and it’s a very big high school. It covers a few blocks, with a big football field and stands, and tennis courts, and a baseball field and softball field. It’s quite- even though it’s an old- you know, I visit my dad and my brother. They're still in Brooklyn. They still live in the same place where I grew up. I look at it now, I see it’s a little dilapidated and not as enormous as I remember. But it’s a very big high school, over 2,000 students, and my graduating class was over 700, I remember, approximately 785.
Were you always interested in science and math, even as a young kid?
Yes, I was. But when I was in the public school, I was interested in everything. I did very well in English and history, and everything. Science, math. I was on the math team. I was one of the writers for the biology magazine. My problem in high school was I wanted to do everything. But I knew I couldn't do everything. And my dad, God bless him, when I had to choose colleges, I applied to a lot of colleges. I applied to Ivy League schools. I applied to Cooper Union. I applied to Brooklyn College, where they had an accelerated MD program, where you do two years undergraduate, and you go right into medical school. And I was accepted by most of them. The Ivy Leagues, I was only accepted by Columbia. But my dad, God bless him, he kind of rapped me on the head, and he said, “You're going to Cooper Union. It’s free.” So that’s how I became a chemical engineer (laughter). And it worked out. So, I have no regrets. It worked out.
What year did you start at Cooper Union?
And did you live on campus, or did you commute from home?
No, when I went to Cooper Union, there was no campus. I think they had a tongue-in-cheek thing in the Cooper Union catalog in the 1980s, "New York City, the Cooper Union campus.” Because there was no Cooper Union campus (laughter). There was no quad, no campus. It was an engineering building, an art and architecture building, which is still there; that’s called the Foundation Building. It’s very famous. That was the original Cooper Union building, from about 1859. And that’s the building, and they still do it to this day, they get excellent public speakers, and they make talks available to the public for free. They call it the Great Hall in the Foundation Building, which is the art and architecture building. That’s around East 8th Street and 3rd Avenue or 4th Avenue. That’s still there. And then they had a little administration building. And since I graduated- I got my bachelor’s degree in ’85 and I got my master’s degree there as well, they demolished the engineering building and the administration building, and they made new engineering and administration buildings. But the Foundation Building, they'll never touch. That’s a historic building. That’s still there. So, it’s still three buildings, but now they have a new engineering building and a new administration building. And since I graduated, they built a dorm building across the street. So now they actually have a dorm, and now, from what I- I'm somewhat active with the Alumni Association—I don’t know if all, but a lot of the students now live in the dorm. So, it’s still not really a campus, but now they have a dorm building that they never had when I was there. When I went, and for over one hundred years, it was a commuter school that drew primarily from New York City, and everybody took the subway and lived at home. So, it was very frugal college experience (laughter). There was no tuition. It was and it still is an excellent school, but there was no campus, and there weren’t really a lot of extracurricular activities (laughter).
Evan, was it a purely technical undergraduate experience? Were there any humanities classes that you were able to take?
Oh, yeah. We had requirements- I remember taking humanities in my freshman and sophomore year. I remember taking a course, a humanities course, a history of science, I think as a junior (laughter). But it was primarily technical, but we did have humanities courses. Yes, yes.
And how did you go about choosing a major among the sciences?
Well, I mean, you know, my dad pushed me into Cooper Union, which worked out. But I knew right away that chemistry was my favorite. In Cooper Union, it was and is a tiny school. It’s 1,000 students altogether, and that’s art, architecture, and engineering, all combined. And it’s about something like 250 engineering students, all together. Something like that. But they offered chemical engineering, electrical, mechanical, civil, and then they had some general engineering degree. And I knew out of those, I wanted chemical engineering, because I loved chemistry. I did love and I still love chemistry. So, I knew that it was going to be chemical engineering if I went to Cooper Union.
What kind of laboratory or internship opportunities did you have as an undergraduate?
Well, because it was such a small school, there weren’t tremendous- I mean, we had required labs that I remember very fondly. And because it was a free school, and it was primarily a teaching school, some of the professors did a bit of research, and that’s why they have a master’s program, that I participated in. But it was primarily a teaching school. But we did have undergraduate labs, and they were terrific. You had to do a tremendous amount of work. And because it was a free school, they loaded onto us many, many courses. We typically took eighteen or twenty credits a term, and they made a lot of the courses one credit, one and a half credits, two credits. So, a typical term that I remember, we would take six or seven courses, because a lot of them were lab courses that were only one or one and a half credits. And even though they were only one or one and a half credits, they were like a four-credit course with a lot of work. And I loved them. I was very excited about them. We had to write lab reports (laughter). We had to take the data. And it was typically old but working equipment. Oh my goodness, I remember a physics lab with cat fur, and we would charge up a pole, and we would have the gold leaf- I forgot what’s that [an electroscope], to measure electric charge. And that was from the 1930s, but it worked. I remember a chemistry instrumental analysis course when I was a junior, that I remember with very happy memories. It was graphite tube atomic emission. There was a little graphite cup. You had to pour the powder sample in the graphite cup. You would ignite the sample in the graphite tube to ungodly high temperatures so that you would atomize the sample and get the atomic emission lines. And a camera with bellows, I remember this, with a hood and bellows, and it had to be from the 1920s or 1930s, with a glass plate. And we had a darkroom. We had to develop the glass plate in the darkroom to get the atomic emission lines. Then, the coup de grâce—I was and still am very nearsighted and half-blind (laughter)- we had to take the developed- I was able to successfully develop the photographic plate and get the emission lines. Then- it was called a densitometer, to try to get the thickness, the darkness, the thickness of the emission lines. And from Beer’s Law, the intensity of the emission line is proportional to the concentration of the sample. I remember with the help of my lab partner, who was much better at seeing the lines, we got very- passably or good results. And that inspired me all the way to the present time, in doing trace and minor element research on coal at the Department of Energy. I still remember that and I remember in trying to develop sorbents years ago, it was my inspiration. Because, you know, we got the challenge from one of our funding managers, this was about twenty years ago, “Come up with a sorbent to remove mercury, arsenic, selenium, phosphorus, all these trace toxic elements, from coal-derived syngas, when you gasify coal.” And you know, there’s a lot of sorbents that will remove these things—common sorbents like activated carbon but they'll do it at room temperature, or near room temperature. He wanted something that would work at very high temperatures, 200, 300, 400 degrees C. Four hundred to 700 degrees Fahrenheit. Most sorbents fail miserably at those high temperatures. But that inspiration, from when I was an undergraduate, that ungodly old apparatus, the graphite tube atomic emission, when I searched the literature, the more modern literature on graphite tube atomic emission, one of the problems that they have when they analyze for the trace volatile elements in these powdered samples, they don’t go from room temperature to atomization temperature in one step. That, I misremembered. What they do is they typically first- they dry the sample at 100 degrees C to remove the moisture. Then they go up to about 400 degrees C to pyrolyze and devolatilize all the organics, to get rid of all the organics. Then, they go from 400 degrees C to ungodly- you know, thousands of degrees C—atomization temperature to get the atomic emission lines. And what I found out is over the last thirty, forty years in the analytical chemistry literature, they deliberately dope the graphite tube with noble metal salts. Why do they do this? What they found out from bitter experience through about the mid-1980s, after I graduated from (laughter) Cooper Union, we didn't do this when we did the experiment as an undergraduate, they doped the tubes with palladium chloride or gold chloride, or iridium chloride, or platinum chloride solution, these noble metals hold on to the trace elements, mercury, arsenic, selenium, that are present in the powdered sample, they’d normally lose them when they dry at 100 degrees C and pyrolyze and remote the organics at 400 degrees C. And a lot of times, that’s not a concern, if you're not measuring for those. But if you really want to measure for this, you need something to hold on to them before you go to atomization temperature, to get the emission lines. And that little trick has been used commonly since about the late 1980s on. And there’s a million papers in the literature. They call it the graphite tube modifier. In the analytical chemistry literature, they call it a modifier. I call it a sorbent. Its job is to hold on to those mercury, arsenic, selenium- these volatile elements in the powdered sample, when you dry and pyrolyze, so that you can release them when you atomize at the thousands of degrees C to get the emission lines. That little trick, when I read it, I said, “Ding, ding! There’s my sorbent for removing the trace elements from the syngas.” And I have a lot of cockamamie ideas. As I said, most experiments and most ideas don’t work (laughter). That one actually worked. I did a dance in Pittsburgh. I was so happy. We published dozens of papers on this. We have a couple of patents on this. And we licensed this to Johnson Matthey. The license now belongs to Johnson Matthey, and we did sixteen pilot-scale tests at a gasifier in Wilsonville, Alabama, that shows, in real syngas, up to 400 degrees C, the palladium sorbent removes one hundred percent of the mercury, arsenic, and selenium from real syngas. We scaled up from my ten-milligram sorbent packed bed reactor using simulated syngas to a ten-pound bed of palladium on alumina beads in a large, packed bed, with a slipstream of hot syngas passing through for weeks at a time. So that’s one of my few crazy ideas that actually worked and went from tiny lab scale, ten milligrams of sorbent in what we call a packed bed. A packed bed is just a little bed of powder. I do it in a quartz tube. I keep it on a piece of quartz wool just to keep it in place. I use a clamshell furnace. And later, I'll send you some pictures and some of our papers. And I use as a screening method, and I mentioned that I do all my experiments typically at very tiny lab scale, a packed bed reactor is a fancy-schmancy term for a tube, a quartz tube, a quarter inch at a diameter. And if you blow in it, that’s about the flow rate that I use, sixty mL per minute, a very small flow rate. But I endeavored, in the case of the syngas, to use a realistic syngas with carbon monoxide, hydrogen sulfide, hydrogen, carbon dioxide, and typically, depending on the contaminant I was interested in removing, mercury, arsenic, selenium, in the form of elemental mercury, arsine, hydrogen selenide. And I would put it through the packed bed, and I would try to have a detector on the back end to see, in real time, if I'm removing it. Sometimes that wasn’t possible, so I would just expose it for six hours, send the used sorbent to a lab onsite in Pittsburgh; they would digest it and tell me how much it picked up during the six-hour experiment. So, these were simple-minded screening experiments, but if you do them rationally, you can learn a lot, and you'll quickly see which sorbents have promise and which don’t. So, I did that for many years with syngas, when you gasify coal. What is coal gasification? I'll send you stuff on that. Coal gasification is a very ancient technology from the 1800s, where you take solid coal and you try to make a useful gas out of the coal. Typically, you do what’s called gasification. It’s the carbon steam reaction-carbon plus water at high temperatures and pressures make carbon monoxide and hydrogen. That’s the stoichiometry. Yeah, carbon plus water goes to carbon monoxide and hydrogen. And that mixture of carbon monoxide and hydrogen is called syngas. And it’s very useful, because first, you can burn that syngas like a synthetic natural gas. That’s why it’s called syngas. And that has been done over the years. There’s some power plants- there was one in Tampa that I think ran until recently, for many years, supported by the Department of Energy, that made syngas and burned it to make electricity. But the more interesting thing you can do with syngases, you can take that syngas and then use catalysts and then make either useful organic chemicals like methanol, or with the right catalyst, all the way up to synthetic gasoline. And that has been done also for many decades, since the 1930s, in Germany and in the United States. For many decades in South Africa, when it was a pariah nation, because of apartheid, they relied on their own coal resources to make their own liquid transportation fuels. So, it’s a very interesting technology, and I spent about ten or more years trying to clean up the contaminants from syngas with sorbents. And then before that, I tried to clean up the flue gas. The more common technology, at least in the United States, is you don’t gasify the coal typically in the U.S., but you do around the world. But in the U.S., you typically burn the coal. Most of the coal that is produced in the U.S. over the last fifty years is burned to make electricity. And when you burn the coal, the resulting exhaust gas is called flue gas, primarily carbon dioxide and nitrogen, because you're burning it in air. Air is mostly nitrogen, almost eighty percent nitrogen. So, when you burn coal in twenty percent excess air at a power plant for complete combustion to make electricity, the flue gas is typically seventy-three percent nitrogen, thirteen percent to sixteen percent carbon dioxide. Depending upon the sulfur levels in the coal, between 100 and 2,000 ppm of SO2. And I think I sent you a little summary of this, but I'll send you a summary of this. You have nitrogen oxides, because of the nitrogen in the coal, as well as the nitrogen from the air. One’s thermal NOx, the nitrogen in the air, from the high temperature. Even though it’s inert, at the combustion temperatures, 2,500 degrees Fahrenheit, you will form NOx from the nitrogen in air. In addition, the nitrogen in the fuel, also results in NOx. So, there’s nitrogen oxides typically on the order of 100 to 500 ppm in a typical untreated coal-derived flue gas. There’s hydrogen chloride in the flue gas, because of the chlorine in the coal. There’s a small amount, on the order of 20 parts per million, carbon monoxide, because of incomplete combustion. There’s plenty of moisture, because of the moisture in the coal, and the combustion of complex organics present within the coal. You have some moisture produced from the combustion of the carbon, hydrocarbons in the coal. You typically have about- depending upon the coal, if it’s a high rank coal, a bituminous coal- coal is graded based upon its rank. How old it is, how long it sat in the earth and “cooked” under elevated temperatures and pressures. It all originates from clean biomass, the ancient fern forests and forests from millions and hundreds and millions of years ago. But as it decomposes and compresses over time and temperature and pressure in the Earth’s crust, the lowest ranked coal is lignite. And those are young coals, only a few million years old, and they're near the surface. And they have a lot of moisture. They're out west in the United States, in North Dakota, South Dakota, Texas. They can have as much as forty percent moisture. And they have a low heating value. And they have a lot of complex organics, which they're a very interesting coal. And they are burned to make electricity, because it’s abundant and nearby, but it’s a lot of moisture and it has a low heating value. The higher-ranked coals sit in the Earth’s crust for longer periods of time. Instead of a few million years, many millions of years- tens of millions of years, or even hundreds of millions of years. These are the sub-bituminous and the bituminous coals. They have less moisture, they're older, they're more graphitic in nature, and have less volatile matter. You know, when you analyze coal in the ancient method, they classify the coal based upon its fixed carbon, its volatile matter, its moisture content, and its ash. This simpleminded classification scheme from the 1800s is still very widely employed, because it’s very useful. When they analyze the coal by an ASTM method that probably dates back really from more than 100 years ago, they dry the coal at 100 degrees C. They measure the weight loss; that’s the moisture content. They assign that as the moisture content. Then they pyrolyze the coal. They heat it in the absence of oxygen to about, this is off the top of my head, around 600 degrees C, and they measure the weight loss. And they'll generate tars, and they'll generate gases like carbon monoxide and hydrogen. They call that the- the weight loss, they assign that the volatile matter. These are the complex organics, especially in the younger coals, that thermally decompose at 600 degrees C. Then they'll go up to about 900 degrees C, in air, and they'll burn the remaining coal that’s left. They call that, they measure the weight loss, that’s the fixed carbon. And this is the more ordered graphitic carbon that’s especially prevalent in the older coals, like the bituminous. And I'll tell you in a minute, they have what’s called anthracite. That’s even older. But that’s a rarer coal. That’s in the eastern United States, and eastern Pennsylvania, and I believe a bit in Rhode Island. These are very old coals, 400 or 500 million years old, from sometimes deeper in the Earth’s crust. And they're very beautiful shiny black rocks. They're ninety-eight percent carbon. They're very ordered, very graphitic in nature. And we're finding- we're doing research- they're very useful if you want to make graphite, or graphene. Because they're already well on their way. They're already a very ordered carbon with very little moisture, very little volatile matter, very little ash. And then, yeah, once you burn the carbon, the coal, at 900 degrees C, whatever is left, you measure the weight loss; that’s the fixed carbon. And whatever’s left is the ash. Those are the mineral oxides that came from contacting the original organic matter with the Earth’s crust, and sediment, and streams and oceans. And depending on the coal, it can have a small amount of ash. Like the anthracite might only be one percent or two percent ash, but another coal, like a younger coal like the lignite or even the bituminous, they're typically on the order of ten percent by weight, ash. So why did I get into this tangent talking about coal? Oh, yes- I mentioned that ten years of my research was the syngas, cleaning up the syngas. But the first ten years, or really the first fifteen years of my research, was cleaning up the flue gas. Because the overwhelming majority of the coal that’s produced in the U.S. really over the last one hundred years, certainly the last fifty years, is burned to make electricity, and you're making flue gas. And I think I sent you a little abstract that gives a brief summary. You burn the coal in twenty percent excess air for complete combustion, typically at around 2,500 degrees Fahrenheit. Very short residence time. I'll send you a paper that we published a few weeks ago that describes this is great detail (laughter). And you know, you extract the heat along the combustion path. And this is a one hundred- 120-year-old technology. The power plants of today aren’t very different than the power plants from the 1920s. The only real significant difference is first, on the back end of the power plant, thankfully, thank God, there’s a lot of pollution control equipment to remove sulfur oxides, nitrogen oxides, the mercury, the particulate matter. Back in the bad old days, one hundred years ago and even probably sixty years ago, a lot of this was spewed uncontrolled into the environment. And the way they tried to control it and I'll use air quotes- “to control it,” was having tall stacks to disperse it, which is not really controlling it. But thankfully, over the last fifty years, these have been very stringently controlled, and we can now say that we remove, in a modern power plant, close to one hundred percent of the sulfur oxides, nitrogen oxides, mercury, and particulate matter. There’s always room for improvement, and I'll send you papers on flue gas. Flue gas is an extraordinary complex stew. You always want to shoot for as close as you can get to one hundred percent. And those are the primary pollutants. But if you look with a magnifying glass, you can study flue gas as well as syngas for thousands of lifetimes. Because coal is so complex, when you either burn or gasify it. I list the major species and the minor species- I'll send them to you, if I didn't already send them to you but there’s always more that you could study. I know our colleagues at EPA study furans and things that we don’t typically study at DOE that are present at extraordinary low concentrations. You know, very difficult to even measure ten to the minus fifteen, or ten to the minus thirteen. We typically can’t measure those concentrations in our labs. We’re happy if we can measure part per million. With our ICP mass spectrometer and the right digestion, we can get extraordinarily low detection limits, but we typically can’t get those type of fantastic low detection limits. But yes, you can study flue gas and syngas for thousands of lifetimes, happily, because they're such complex and interesting stews.
Evan, given the fact that chemical engineering is such an industry-specific job, did you ever think to go into industry as an undergraduate and not go the academic track with a PhD?
You know, I always had the vague notion as an undergraduate, and as an undergraduate, you don’t really know the ins and outs. Even though Cooper Union was a small school, and it’s a terrific school, you don’t really know the ins and outs. You know, what does a professor really do? You see them teach your courses, but you don’t know the nitty-gritty, whether they're at a research school where they're spending a lot of time writing proposals to get funding for their research and they have a large group of graduate students working in their labs. Or the example that I saw at Cooper Union, they were mostly teaching courses. There were a few that were active, and they had a couple of master’s students, and they did small research projects. And I have happy memories, my advisor at Cooper Union, Professor S.I. Cheng, I hope he’s still alive. If he is still alive, he’s one hundred years- I know he was born in 1920, so if he is still alive, he’s one hundred years old. And I asked a couple years ago, and they said he was still alive, so I'm very happy. But he would have a couple of master’s students. He would get funding from the Department of Energy. And in a happy accident, my master’s thesis was on coal gasification. He had many patents, and he was trying to commercialize them. So, my job as a master’s student at Cooper Union was to try to do a pilot plant design on paper for one of his patents on coal gasification. He tried to co-gasify coal, municipal solid waste from landfills, and municipal sewage sludge, together in a gasifier, a rotary kiln, which is just a tubular reactor. It’s not a packed bed reactor; it’s an empty reactor that rotates. They use it in the cement industry. And he tried to co-gasify these three unloved materials. He wanted to co-gasify lignite, which is the cheapest, lowest-ranked coal, because it has the high moisture content, from Texas. He wanted to co-gasify that with municipal solid waste and municipal sewage sludge. And in the context, it was in the 1980s, there was a garbage crisis and a sewage crisis in the mid-1980s, so it was very timely. I don’t know if you remember, it was a big story in the mid-1980s, they had the garbage barge to nowhere.
It was from New York City, a lot of the trash from the big cities on the East Coast, they didn't have space. There were and are big landfills in New York City, Staten Island, and then off the Belt Parkway- I forgot the name of it; they closed it, near Starrett City. It was enormous. You could smell it from two or three miles away. And I feel bad, these are beautiful sections of Brooklyn and Queens, but they had to live near a massive, enormous landfill, which I believe they subsequently closed and covered over, and they put it to another use. But they ran out of space in the mid-1980s, so they had to ship their garbage to eastern and western Pennsylvania, and all over the world. There were a lot of third-world countries that actually took our garbage. People didn't know that. That was a dirty little secret. But in the mid-1980s, one of those garbage barges, I think it was supposed to go to either Italy or Nigeria, they said, “No, we don’t want your garbage.” And this poor garbage barge made a trek around the world because a lot of countries refused to take it. So, you know, it was timely, if you could do something other than just dump the garbage in a landfill. And what they did with the sewage sludge in New York City in the mid-1980s, they dumped it off the ocean, very close to the shore. Which is obviously not the best thing to do with it. So, I was very excited to work on this. It was mostly a paper study. I got papers from the literature on what you might expect when you gasify lignite, sewage sludge, and garbage. There is always a big literature on gasification and pyrolysis. And I used that to make a rough mass balance, assuming similar yields, that I found in the literature experiments. And I had the known composition of the Texas lignite, so it was essentially a gargantuan mass and energy balance. And because it was the mid-1980s, I did everything by hand. So, it was a very good learning experience, a very tedious but good- you know, I knew the end goal. I did very well as a chemical engineering undergraduate. I took plant design, mass, and energy balance. I knew exactly what had to be done (laughter). And I was very good in kinetics and all that. But I knew on paper this was essentially an enormous bookkeeping analysis (laughter). I'll send you- for giggles, I'll send you- I have it as a PDF of my master’s thesis.
And it was a good learning experience, and I ended up doing it- I stayed there for a year, and then I got accepted to the PhD program at the University of Rochester. So, I was essentially all done. I took all my courses, thirty credits. I had it basically all done on a giant pile of scrap paper, but I had to clean it up and make it a presentable report and a presentation. I ended up doing that three years later (laughter). I flew in on a weekend, I presented it, and I successfully defended it. But it was a good learning experience, and I look back on it fondly. And it ended up helping me. When I now teach the petroleum and natural gas processing for the graduate students at Pitt, I'm very confident when I talk about pilots and plant, I'm not afraid about a heat exchanger or different reactors or doing mass balances. Now they typically do it with spreadsheets, and there’s off-the-shelf programs for chemical engineering. When I was there, it was called FLOWTRAN, which I didn't bother using. I learned how to use it, but I didn't use it. I did it all by hand. But now there’s Aspen, and there’s more sophisticated programs that, if you know what you're putting in, you know the conditions, it’ll try a first-pass mass balance for you. And it’ll also try to do the sizes and the cost. I did that all by hand. And there’s crude methods in the literature, they call them first-order estimates, where if you can find similar plants, you can get the cost factors, which are inflation factors and size factors. They have empirical scaling relationships. So, if you know the size of one plant of this size, you can scale it to a smaller or larger one. So, I had to do that for absorption towers, reactors, different pieces of equipment. And I was able to find that driving myself crazy, looking across the literature. And this was before you could do computer literature searches. So, it was a very good experience. I spent a year essentially sitting in the library or going to the AIChEs Library, which was near the UN at the time. It was a very good learning experience. Not to be discouraged. Even though it looks big on paper, if you break it down into small pieces and you keep working on it, even if it’s a little bit every day, all of a sudden, you'll be surprised, after a few months, you're well on your way. So it was a good learning experience that I look upon fondly. And also, it actually had relevance, because I ended up doing about ten years of research at DOE on cleaning up syngas from coal gasification. So it’s a small world. Yeah, that project was funded to my advisor through our Morgantown site in the 1980s. We were separate sites. I started in 1996 in DOE. But in the 1980s, the Morgantown site was called METC, Morgantown Energy Technology Center. The Pittsburgh site was called PETC, Pittsburgh Energy Technology Center. And they were around for about one hundred years. The Pittsburgh site historically did research and mostly funded outside research on coal combustion, the coal-burning power plants. The Morgantown research center was around also for many decades. They historically did research on gasification and mostly funded outside research on gasification. And my advisor, I didn't know it at the time but I found out later, he was funded by the Department of Energy by our Morgantown site in the 1980s. So, it truly is a small world. And then when I went to Rochester, I ended up doing research on catalysis, trying to learn the mechanism of different catalysts for burning and converting hydrocarbons like methane- primarily methane. Methane, typically you burn natural gas to make electricity to do your cooking, your home heating, your hot water heater. But the more interesting thing with methane, this is from the 1980s and the 1990s when I was a PhD graduate student, the more interesting thing with methane is if you could ever convert it to more valuable chemicals, you would have a Nobel Prize-winning discovery. Because, you know, methane is relatively abundant. Natural gas is a relatively clean fuel. Compared to coal, it’s infinitely cleaner than coal, certainly. There’s contaminants in natural gas. There’s hydrogen sulfide, there’s a trace of mercury, there’s moisture, there’s nitrogen, trace particulates. It comes from the ground, but it’s overwhelmingly methane, which is a beautiful, simple, clean fuel. But you do have to process the natural gas before you use it. But if you could ever convert the methane directly to things like methanol or ethane or ethene, that would be a whole industry. Because most of our common consumer plastics are polyethylene and polypropylene, and they're derived often from petroleum. But if you could do it from natural gas, that would be a great invention. And in the early eighties, before I started my PhD program, two German scientists, Keller and Bhasin, they discovered catalysts that can convert methane to ethane and ethene. And that was a big discovery, because if you could ever do that efficiently, you'd have a multibillion-dollar invention, because you could make plastics directly from methane. They discovered catalysts that worked, but they had low yields. They were mostly making CO2 and CO, and you know, modest five percent yields of ethane and ethene. So part of my thesis project was to try to make a better catalyst and learn how the catalysts worked, to take methane to ethane and ethene. And I had some modest success. And also to look at other catalysts that directly burn the methane to CO2 and CO, and also to look at other catalysts that convert other hydrocarbons like methanol to industrially relevant chemicals like formaldehyde, which is also a big consumer commodity chemical, because they use that to make carpeting, different fibers, to take methanol to formaldehyde. So that was a good learning experience. My research advisor, God bless him, he passed away about four years ago, Howard Saltsburg, in the University of Rochester. Off-the-chart brilliant. Very brilliant. He knew his stuff. But he was very demanding, and his people skills were not so good (laughter). But it was a great learning experience (laughter). It has helped me tremendously. My catalysis background- I've done research at DOE on catalysts. I've taught the kinetics graduate course and catalysis course at Pitt. And a catalyst and a sorbent are very closely related. I say they're first cousins. They're extremely- everything you learn about catalysts are directly transferable to sorbents. And most of my research has been on sorbents. So, it was a tremendous background for what I do now at the Department of Energy. It’s always going to be a tough experience. Typically, you're there for five years, if things go well. And you're focused on your research project. Yes, you have to take your courses, but that’s not a limiting step. The really limiting step is always getting your thesis research done and making your advisor happy (laughter). If your advisor is happy, you're going to get your PhD. I always say it’s a kangaroo court. And I tell nervous students- I've served on several PhD committees. They allow me to be on committees for outside students. I always tell them, “If your advisor is happy, you don’t have to be nervous.” You know, “Do a good job. Do the best you can. But you're going to get your PhD. You don’t have to lose sleep. Just do a good presentation and make your advisor happy.” But it adds unnecessary stress. I'll say that. So I give these undergraduates that I have as summer interns in my lab, I tell them, “Not only do you want to pick an advisor that’s doing research that you find interesting and exciting; you'd better find it exciting, because you're going to be doing it probably for five years, if you're a PhD student. But also, someone that looks like they can get along well with people.”
Evan, could you have stayed at Cooper Union for the PhD?
No, no. At the time and still, the master’s degree was the highest degree that they offered. I think into the early 1970s, they had a small PhD program, but I believe that was eliminated. It’s such a tiny school, and historically a free school. That changed about five or ten years ago. They ran into financial trouble, so now they charge tuition. But they couldn't afford- I always say that that was a mistake, because a lot of times, undergraduates are attracted by the great research program and the famous professors. They'll always be attracted to Cooper Union because it’s very well known in New York City, and it’s historically a free school. So, they'll never have a problem attracting students, but I always thought that that was a mistake. But I knew back then I wanted to be a professor. I had to go on. So, I went to the University of Rochester, which is a beautiful school. It has a campus. It’s a small university, very beautiful campus. And Rochester, it has an excellent chemical engineering program, I would say top twenty. But they're even more famous for their music school. The Eastman School of Music is very famous. And they're very famous. They have a very famous chemistry program that I would say might be top five. Chemical engineering is outstanding; I would say it’s top twenty. They also have a famous kind of unique optics program. There’s very few major optics programs in the U.S. They’re one of the few. They have a very famous optics program for undergraduate and graduate. And they also have a laser lab that’s famous. So that was a good experience. Even having a tough advisor, it was a good experience.
Evan, what did you want to do after you graduated, after you defended your thesis?
I wanted to be a professor, as I mentioned. But I kind of had unrealistic dreams. Just like I applied to Ivy League schools out of high school, I applied to Ivy League schools coming out of Rochester. And you know, you have to have a tremendous publication record coming out of your PhD to go into an Ivy League school as a new assistant professor. And what I didn't know at the time is you typically have to be a postdoc for a few years somewhere else and have a nice publication record. Then, you might have a chance to go and become a new assistant professor at an Ivy League school or at a Stanford, or something. I was so naïve. But, you know, it was a good learning experience, I ended up taking a postdoctoral position at the Department of Energy in Pittsburgh. I had heard of the Morgantown lab; I had never heard of the Pittsburgh lab. Back then, they were separate. It was the Pittsburgh Energy Technology Center. That’s where I started working in 1996. I answered a little ad in the back of Chemical & Engineering News. That’s how (job searches) were done back then. They still have those, but now most of them are online. And they were calling for a postdoc, with a background in catalysis and sorbents. I said, “This is me!” I sent it in by mail. Back then, you did everything by mail (laughter). Snail mail. I didn't hear anything for about two or three or four months. I kind of forgot about it. And then all of a sudden, I got a call out of the blue from Henry Pennline, who ended up being my research supervisor for three years (laughter). And he basically said, “We want to hire you.” He interviewed me over the phone for a half hour. And you know, it went well. So, I said, “Do you want me to visit the lab?” Because I thought, “This is kind of strange. They want to hire me over the phone?” I forgot about answering the ad and sending my resume several months earlier. He said, “No, it’s okay” (laughter). So, I looked them up, and I said, “Oh, they're a government lab. They look legitimate. It’s certainly my background. It sounds exciting.” He wanted someone to come up with sorbents to remove mercury from power plant flue gas. I said, “I know I could certainly do this.” So, I took a chance and I moved five hours down from Rochester to Pittsburgh. And I did three years as a postdoc, and now about twenty-one and a half years as a federal employee.
Evan, what was your first work as a postdoc?
(Laughter) My advisor, he retired a few years ago, but I’m still in contact with him. I consider him not only an excellent colleague, but a terrific friend, Henry Pennline. He was a terrific advisor. He told me my first task was a literature survey. And that’s one hundred percent correct. When you're starting a new field of research, before you jump in and do experiments, especially if you have the time, and you know, we have the time as federal researchers find out what has been done previously. And I did a very extensive literature survey. I found out what was done previously in removing mercury from other fluids, other- there wasn’t a lot on flue gas in 1996, because there was no regulation. EPA hinted in 1990 that they would potentially eventually regulate the coal-burning power plants for their mercury emissions. They ended up issuing the regulation in 2016, which is twenty-six years later (laughter), which shows you how the timeline can be very slow for regulating, especially a minor pollutant like mercury, a very important but minor pollutant like mercury. The timeline from signaling they're going to eventually regulate it because it’s not only a scientific process at EPA; it’s also a political process. Twenty-six years later, they issued the regulation. And the regulation wasn’t fully implemented until about now. Until about 2020, 2022. So really over a period of thirty-two years (laughter). They said in 1990 they were going to eventually regulate the mercury emissions from coal-burning power plants. And why did they do that? Because previously in the U.S., the big mercury polluters were the incinerators, the medical incinerators and the municipal solid waste incinerators, and the hazardous waste incinerators. Hospitals used to have mercury thermometers and monometers. All sorts of terrible things would go into the waste. And when they burned that, that was released into the flue gas. They were the big mercury polluters in the 1970s and the 1980s. Mercury used to be in a lot of consumer products. It used to be used as a preservative in paints and in pigments. It used to be used actually in medicines, and still used as a preservative for vaccines. It used to be in a lot of batteries. But by and large mercury has been removed from most consumer products- an exception being fluorescent lamps still contain a few milligrams of mercury and must be disposed of properly. But the big mercury polluters in the U.S. in the 1970s and the 1980s were the incinerators, the medical, municipal, hazardous waste incinerators. But because mercury was phased out of a lot of consumer products, thank goodness, and because they regulated the incinerators in the 1980s, their mercury emissions went way down. So, then the next big polluter on the list, not that their pollution increased; just because they took care of the big polluters, were the coal-burning power plants. So, they signaled in 1990, “We intend on eventually regulating the coal-burning power plants. They're the next one on the list.” At the time, in the 1990s, they were putting out about fifty tons of mercury up the stack per year in the United States from burning coal to make electricity. That sounds like a lot, but at the time, we were burning a billion tons, a billion tons of coal to produce roughly half of our electricity in the 1990s. This is the 1990s. There’s only a tenth of a part per million of mercury in a typical coal. So just from the mass balance, a tenth of a part per million of mercury in a typical coal, and you assume it’s a volatile element, it likes to be in the elemental form, when you burn it, if it goes all up the stack, by mass balance, a tenth of a part per million times a billion tons of coal, that would be one hundred tons of mercury per year going up the stack. But the existing pollution control devices at the power plant, for SOx, for NOx, they had wet scrubbers to remove the sulfur oxides. They have catalysts to take care of the nitrogen oxides. They have filters or ESP, charged plates, to take care of the particles, the ash particles that are entrained in the flue gas. They naturally remove very roughly, about fifty percent of the mercury. So, EPA estimated in the 1990s that fifty-one tons were going up the stack. Roughly fifty were being captured either by when you- before you burn the coal, sometimes you very crudely clean it. You remove some of the ash. Some of the mercury was removed there. And some of the mercury was removed by the existing pollution control devices that were already at the power plants for sulfur oxides, nitrogen oxides, and particulates, the small, entrained fly ash particles that are removed at the back of the power plant. So that was the challenge, how do you remove as much of that fifty-one tons of mercury going up the stack each year from the coal-burning power plants in the 1990s. You can do it several ways. My favorite way is a sorbent. A sorbent is a solid that will adsorb a contaminant on its surface and bind it there so that you can remove it. And it’s related to a catalyst, because a catalyst typically does the same thing, but with a catalyst, once it sticks on the surface, you often want to convert it to something else. With a sorbent, you're just happy that you got it stuck onto the surface. And either you could regenerate the sorbent, either with heat or acids, and reuse it again and recover the mercury, or, if it’s strongly bound enough, if it’s sufficiently strongly bound to the surface, essentially permanently bound to the surface, and it’s cheap enough, you could dispose of it in a permanent waste facility. And with a cheap sorbent that you have confidence that you strongly bound the mercury, sometimes you promote activated carbons with sulfur, you'll end up catching the mercury as a mercuric sulfide. That’s a very stable compound. That’s how mercury is found in the Earth’s crust. It’s not completely inert. You can convert mercuric sulfide to other things. But it’s relatively stable. And often times, if you can show that it won’t easily leach or volatilize, you can get permission to dispose it in a permitted facility. But that’s for a cheap sorbent. For a more expensive sorbent, you'll want to regenerate it and reuse it and recover the mercury and take care of that somewhere else. But you could also capture the mercury with what’s called a scrubber solution. That’s an aqueous solution just like they use for the sulfur oxides. For the sulfur oxides, they use aqueous alkaline solutions, essentially lime water, calcium hydroxide. It’s an acid-base reaction. The sulfur oxides and the SO2 and SO3 in the flue gas react with the aqueous basic solution to make calcium sulfate. And that’s widely used in the United States over the last thirty, forty years. And as a matter of fact, the byproduct from that calcium sulfate is gypsum. They use that to make synthetic wallboard, and it’s used in a lot of home construction. But you have to be careful- is there any trace contaminants that are picked up in that byproduct? Because it’s being contacted with the dirty flue gas. It is almost one hundred percent calcium sulfate, but you just have to be cautious. And DOE has funded studies to make sure there’s not hazardous mercury or other things in that gypsum. But yes, you can use that same aqueous solution for the sulfur oxide that has been used for thirty, forty years at the power plants. You can try to catch the mercury in that. But the problem is, when you burn the coal, a lot of the mercury ends up in the flue gas as elemental mercury. If you look on the periodic table, mercury is near palladium and copper on the periodic table. These are noble metals. It’s happy in the elemental form. And elemental mercury is exceedingly water insoluble. It won’t go into solution. So, if you have elemental mercury in your flue gas, the existing wet scrubber that may be in your power plant to capture the sulfur oxides won’t capture the elemental mercury. But if you can oxidize the mercury, things like mercuric chloride, they have water solubility. So, if some of the mercury in your flue gas is in a compound form like mercuric chloride, that will dissolve in the scrubber solution, and you can use the existing wet scrubber to try to remove the mercury. And as a matter of fact, that is a strategy that some of the power plants try to use. But the problem is they need to have a coal that’s either high in chlorine, so that when they burn the coal at the high temperatures, a lot of the mercury will end up being water-soluble mercuric chloride. Or, what they've ended up doing in recent years-this is patented commercial technology- they'll treat the coal before they burn it at the power plant. How do they treat it? They treat it either with chlorine or more typically recently bromine salts- you know, with the calcium bromide or other relatively inexpensive bromine or chlorine salts- so that when they burn the coal, they'll oxidize the mercury to mercuric bromide or mercuric chloride. It’ll have solubility, and it’ll either dissolve in the existing wet scrubber and be removed with the sulfur oxide, or, if there’s a little bit of unburned carbon in the fly ash at the back of the power plant, all the power plants have to have either what’s called ESP, charged electrical plates to catch the small ash particles that are entrained in the flue gas at the back of the power plant. Or they'll have what’s called a baghouse, which is just a fabric filter, to catch the small ash particles. If your fly ash has a little bit of unburned carbon, your combustion is not one hundred percent efficient, and that’s very common. That unburned carbon can act as a sorbent, and if you have a flue gas where a lot of your mercury is mercuric chloride or mercuric bromide, that tends to stick on the unburned carbon. So that’s another strategy, that your particulate collection device at the back of the power plant can also remove the mercury, especially if you're doping the coal with bromine or chlorine to drive the mercury in the flue gas to very reactive adsorbable mercuric chloride or mercuric bromide. So that’s another strategy. So as a postdoc, I did this massive literature search. I published what’s called a topical report. And I'll send that to you for giggles. That was essentially a small book that we published, the DOE calls them topical reports. They make them publicly available on our website, and I think through a Government Printing Office as well. I self-published, with the permission of my advisor, we published my literature search on all the research that has been done in recent decades on sorbents and other scrubber solutions for removing the mercury, as well as some of the fundamental chemistry. And I told my advisor back then, “We should write a book on mercury.” I'm a new postdoc. He looked at me like I'm crazy. He was older than me, and he had experience with both good and bad graduate students and postdocs. He said, “Let’s just focus on the project. You can publish your topical report. You can do your experimental research.” Once I did the literature survey, I did experiments in the lab. And, you know, it certainly was not a high-tech lab; it was quartz tubes and old clamshell furnaces (laughter). But I realized- I scribbled it- I'm a big eater, and I'm not ashamed to say, I like eating pizza and takeout in my apartment (laughter), I lived less than a mile from the lab, I had a pizza menu that they slid under the door, and on the weekend, I said, “How am I going to figure out what the best sorbent for removing the mercury is?” I scribbled on the back of a pizza menu. I said, “I could make a little packed bed reactor with the quartz tubes that we do have in my poorly-funded lab.” But the most important thing, though, was that I had good colleagues, and a good- a beautiful advisor. That’s more important than having millions of dollars of funding (laughter). We literally did this on like a $10,000 budget (laughter). So, I scribbled on the back of my pizza menu the quartz tube to be my packed bed reactor with a little bed of sorbent. And we did have- thankfully, we had an old but working mercury detector. It’s called an atomic fluorescence spectrophotometer. And I played with that—because I had never used that in the past. I said, “Oh, it’s a very simple device (laughter). Even I can understand it.” It’s a little quartz cuvette, and it’s a little plumbing. There’s Teflon plumbing inside. And basically, mercury absorbs and re-emits short-wave UV light, 253.7-nanometer short-wave UV light. That’s fluorescence. And I could see, there’s a mercury UV bulb there. There’s a photometer that’s a photodetector that sits on top of the quartz cuvette. And the gas flows through the quartz cuvette. Quartz is transparent to UV light. It’s irradiated by short-wave UV light, the 253.7 UV light coming from a mercury UV lamp. It’s a clear bulb. And then the mercury that’s in the gas absorbs the UV light, and then within about a billionth of a second, reemits the same UV light, the 253. That’s fluorescence. And that’s the basis for detection. There’s a shielded path where the UV light goes to the quartz cuvette. The mercury absorbs in the gas it. And then the photometer sits on top of the quartz cuvette, and it measures the intensity of the reemitted UV light, the fluorescence intensity. And from Beer’s law, the intensity of the fluorescence is proportional to the concentration of mercury in the gas. And this most primitive thing, you know, I'm ten thumbs. My wife makes fun of me that I have the most primitive mechanical skills. But even with my most primitive mechanical skills, it was good that it was a cheap old detector. I was able to take it apart, see how it worked, clean the cuvette, change the bulb. “I know how this works.” And I remember from undergraduate days, I loved physical chemistry. I won the physical chemistry prize at Cooper Union when I was a senior, the Tektronix prize. And I remembered reading about fluorescence (laughter). Even though we weren’t tested on it, I remember reading about fluorescence. I said, “I understand how this works!” And I used that as the detector in the back end of my reactor. So, I had an online detector. Even though it was very primitive and old, and it was probably twenty years old when I used it in my lab in the mid to late nineties, it worked! And I was able to clean it and make sure- replace the bulb. And even though it was primitive, it was exquisitely sensitive, that if it was just mercury and a noble gas like helium or argon, it had extraordinarily low detection limits. This primitive thing, I think back then it was like $5,000, and they probably were able to put it together for a few hundred dollars. It was a photomultiplier tube, a $10 mercury bulb, and a quartz cuvette. It could detect subpart per billion, easily, online, which is an extraordinarily low detection limit. So, I said, “All right, just to get started-” You know, it’s not flue gas, but I could make mercury and argon, or mercury and helium, put it through my bed of sorbent, and see how much is removed. I could measure what’s going in, switch a valve and measure what’s going out of the back of the reactor. And that’s called breakthrough curves. I would hit it with a few hundred parts per billion of mercury, which is not a realistic, that’s an incinerator flue gas that had thermometers and mercury-containing medicines, they would have a few hundred parts per billion of mercury in their flue gas. But coal, which is only a tenth of a part per million of mercury in the raw coal, that in an untreated flue gas is only one part per billion mercury concentration. And I could use- we had a source of mercury called a permeation tube. It’s a drop of mercury in a sealed Teflon tube. And at room temperatures, it was safe to hold. And I would show visitors to my lab, you know, you don’t normally want to hold a drop of mercury. It’s toxic, the vapors. It’s a neurotoxin. You don’t want that in the environment. But at ambient temperature, you could hold it in your hand, because it was a drop of mercury, encapsulated in a sealed little Teflon tube. But if you put that in a glass U-tube, and you put it in an oil bath and maintain a constant elevated temperature and you flow nitrogen over it or argon over it, you can get mercury to diffuse through the Teflon tube at a constant rate, and you could use that as your source, if you want a few hundred parts per billion, or even less of mercury, in a controlled manner. And the way you calibrate them is you weigh them every month, and if you keep operating it month after month, you'll have a measurable milligram weight loss. So, I used that very successfully as my source for the mercury. I didn't invent that. That was known. I borrowed that from the literature. But my packed bed system, which I started where it was just mercury and nitrogen, or mercury and argon, and I was able to get these simple breakthrough curves to do first-order screening of sorbent, I was able to subsequently make somewhat realistic flue gas, putting in CO2 and oxygen and sulfur oxides, and nitrogen oxides. And I did this for three years. I ended up essentially doing another PhD thesis. I screened hundreds of sorbents, but I didn't do it randomly. My friends and colleagues at the Department of Energy liked to razz me. But, you know, they would make fun of me that I was throwing darts at the periodic table, on testing so many different sorbents. And one other wise guy (laughter) friend of mine- he’s still my friend; he was the best man at my wedding- he said I was testing material that I found on the bottom of my shoe. But no! Because I did that extensive literature search, I already had candidates in mind. I saw what was done in the literature. I knew the rough chemistry of the different sorbents that had been looked at in the past. I had the catalysis background for my PhD thesis. I had hypotheses in mind. And I was focused, you know, the most common sorbent in the 1990s and the one that’s actually commercially used, is activated carbon. I knew that activated carbon was going to be a commercial sorbent for the power plants, because it was already successfully deployed for the incinerators, which is a related flue gas, albeit with a much higher mercury concentration. So, I knew that was of interest, so I looked at different carbons. And I tried to make some “homemade” activated carbons, some derived from the power plant where you pull partially burned coal from the furnace. I was very lucky at the time, even though my lab was very primitive, but I never complained because my colleagues were very nice and the research was interesting. And I knew from my graduate school experience, that’s more important than having a fancy lab. If you have good colleagues and an interesting research project, it’s not so important to have a multimillion-dollar lab. So, I was very happy. But even luckier, even though my lab was primitive, we had pilot units on site in the 1990s that burned coal. And they tried to scale our discoveries from the lab, if we could, to the pilot scale. So, I was very fortunate, literally right in the next building, they had a 500-pound-per-hour coal combustion facility. And that was there for about fifty years. They decommissioned it twelve years ago. But that was there when I was a postdoc and when I was a new federal researcher. And that was very fortunate because we learned things from the operation of the pilot plant, how to make cheap activated carbons. That pilot plant was meant to mimic a power plant. We didn't generate electricity, but we burned coal under essentially the same conditions that they do at the power plant, essentially at one over 750 scale. A real power plant would have been much bigger, but we did it at the same temperature, same- the composition of the flue gas was the same, burning the same kind of coals. Everything was the same; it was just smaller. So, things that we learned there, we could translate in the lab, and vice versa. And one of the first things we learned in the pilot plant, when I was a postdoc, was we could easily generate some interesting carbons from the furnace at the power plant. If you extract some of that partially burned coal, which you normally wouldn't do, but if you extract some of that partially burned coal from the furnace, that’s a crude activated carbon! And you can make that essentially dirt cheap! And I tested that, and I showed in the lab, yeah, that adsorbs the mercury almost—not as well, but almost as well, as the commercial activated carbon, and it’s at least an order of magnitude cheaper. And we commercialized that. I wrote papers on that, patents on that, our DOE Thief Process. We licensed that to several companies, and that was very exciting. And for my literature search, I was always focused—I know activated carbons are going to work, and I spent a lot of time looking at different activated carbons, trying to make new, cheaper activated carbons. But I had a background in metal oxide catalysis from my PhD thesis, and searching the literature, I said, “We could come up with other alternatives to activated carbons.” Because I knew activated carbons would work, but you have to use a lot of it. It typically works best at low temperatures, near ambient temperature. When you go to flue gas temperatures, which are typically at least 300 degrees Fahrenheit, even at the back of the power plant, you want the flue gas to be warm, because it has to have thermal buoyancy to go up the stack. And it also has to be above the acid dew point. You don’t want sulfuric acid and nitric acid to condense in your duct work at the back of the power plant. So typically, flue gas temperatures, even at the back of the power plant, are still rather warm or hot. And activated carbon, at 300 degrees Fahrenheit, it’ll work, but you're pushing it to its limit. You have to use a lot of it. So, one thing I knew from the literature was there were a few metal oxides from one hundred years ago they knew would adsorb mercury, specifically manganese oxide. There was an old sorbent called hopcalite, from the 1920s, that I think they used in World War I, or from the nineteen-teens, for gas masks. Manganese oxide is a good oxidation catalyst. It’ll burn carbon monoxide, or it’ll capture many toxic gases, primarily by oxidation. Because manganese oxide, MnO2, it could be reduced to lower oxides, or if it’s really under severe reducing conditions, all the way down to manganese metal. And so, I thought, from that inspiration, there’s got to be a lot of oxides that could capture mercury, from my PhD thesis on metal oxide catalysts from burning methane. And sure enough, I had one of my few hypotheses that actually worked, some of the metal oxide oxidation catalysts for converting methane and for other hydrocarbons, they worked very well. The same way they worked for burning hydrocarbons, the lattice oxygen of the metal oxide (laughter) will oxidize the mercury to make mercuric oxide, and it’ll stick on the surface, and you'll reduce the catalyst to a lower oxide, especially if you're in an oxygen-deficient gas. And I tried that almost right away in my little packed bed, and I found, yes, it works like a charm, and it works exactly how it’s supposed to. In the absence of oxygen, when it’s a catalyst, that's the test on, it’s called- there’s three major mechanisms for a catalyst. When I taught the catalyst course, and I knew this from my graduate student days, the most famous mechanism for a catalyst is the Langmuir-Hinshelwood mechanism. A species A adsorbs on the catalyst, and sticks. Another species B may adsorb on the catalyst, and stick. A and B, they stick to the surface. They combine on the surface to make the product, either C, and then it desorbs from the surface. That’s the classic and the most common catalyst mechanism, the Langmuir-Hinshelwood mechanism. But the one that I was always fascinated in, in grad school, and the one that I played with in grad school and published on in grad school, in my thesis, was the Mars-Maessen mechanism. This mechanism is a metal oxide catalyst for hydrocarbons where the lattice oxygen is really the reagent. So, you have a hydrocarbon, it hits the metal oxide catalyst, the lattice oxygen from the oxide like a manganese oxide burns the hydrocarbon and in the extreme case makes CO2 and reduces the catalyst to a lower oxide or even down to metal. And because it’s a real catalyst, if you have oxygen in the reacting gas, it reoxidizes it back to the original oxide. So, it’s a true catalyst. That’s the Mars-Maessen mechanism. But the test of the Mars-Maessen mechanism is if you run the catalyst in the absence of gas phase oxygen, like in nitrogen, it’ll work for a few hours until you fully exhaust all that lattice oxygen. I did the same thing with mercury. Lo and behold, it worked. I proposed a new mechanism for the mercury catalysts, for the metal oxide catalysts, the Mars-Maessen mechanism, which is an old mechanism for hydrocarbon oxidation, but was a brand-new mechanism for mercury sorbents or catalysts. I published on that. And one of our original papers from our topical report and one of the first papers we published from my postdoc, I think that has been cited about 500 times (laughter). So that was very satisfying. So, I was very gratified, and I told you that my postdoc was essentially a second and third PhD. I screened hundreds of sorbents, I did the literature survey that we published as a topical report, I published several papers on the sorbents, what we learned. We patented and licensed our Thief Process, using the crude activated carbons extracted from the furnace at the power plant to remove the mercury. But also, (laughter) I mentioned that atomic fluorescence detector, that humble twenty-year-old detector that was in my lab. Fortunately, by luck, it was in my lab. I noticed that sometimes when I did the experiments, when it was a mercury and a noble gas, everything worked fine, I could have my online breakthrough curves, I could have my exquisite low detection limits. It worked fine. But I noticed when I tried to make realistic flue gases, when I put things like sulfur oxides and nitrogen oxides and moisture and oxygen, things that are in real flue gas, things didn’t work so well. And because it was such a simple thing, I could take apart the detector. And I saw the quartz cuvette would have these reddish-brown stains. And you know, I'm color-blind, but I knew something was going on. I said, “It wasn’t reddish brown-” You know, I cleaned it with trace metal grades, nitric acid, to make sure it was clean before the experiment. I thought, “What’s going on?” So, I remembered, lo and behold, from my undergraduate days, my undergraduate physical chemistry book, there’s a whole research area from the 1920s and the 1930s; it’s called sensitized oxidation. Elemental mercury, when it’s irradiated with 253.7 nanometer short wave light, can cause all sorts of chemical reactions that I wasn’t fully aware of before I started doing the research. But when I went back to my undergraduate physical chemistry book, I said, “That’s what’s going on! It’s called sensitized oxidation!” The elemental mercury is in an excited state. When it’s in a noble gas, it can’t react with anything, and it just goes back down to the ground state, and it emits the 253 radiation. That’s the fluorescence. But when it’s in a more complex gas matrix, with things like oxygen or water or SO2 or SO3 or NO or NO2, things can happen. When that mercury is in the excited state for on the order of a billionth of a second, yes, it can go back down to the ground state. That’s what happens in a noble gas. But when it’s in a more complex gas, it can collide with things like oxygen, or water, or SO2, SO3, NO, NO2, all the things that are present in dirty real coal flue gas. And instead of emitting the 253.7 fluorescence, it transfers its energy to these other things, and it sets in place oxidation. It ends up, with oxygen, you end up making ozone, and the ozone reacts with the mercury to make mercuric oxide. And that was the reddish-brown stain that I saw in the cuvette. I first thought it was sulfur or bromine from some of my promoted sorbents. You know, I have it in a heated packed bed reactor, and these things can thermally volatilize. Sometimes it would see it on the bottom of my packed bed reactor. I said, “Oh, I'm liberating some of the sulfur from my sorbent” (laughter). And I thought maybe some of it was making it into the quartz cuvette further downstream in the detector. No. I had it tested by my onsite analytical chemistry lab, and I did further literature survey. I ended up getting so excited about it! I'm not a photochemist. I told you, my background is in catalysis and now catalysis and sorbents. But I got so excited about this. I remembered it from my undergraduate days. I saw it was going on right in front of my eyes (laughter). I did the literature survey on that, and I started doing photochemical experiments. So, I said, “This is a problem in the detection of the mercury.” Made my online breakthrough curves. But I said, “If I use my imagination, maybe this is a long-shot way of removing the mercury from the flue gas.” If you irradiate the flue gas just like we were doing in our atomic fluorescence spectrophotometer and the quartz cuvette. It was oxidizing the mercury to mercuric oxide and depositing on the cuvette, which was unwanted in the detector, but I said, “That might be a way of removing it from the flue gas.” So, I took empty quartz tubes, the same empty quartz tubes I was using for my packed bed reactor. When it had ten milligrams of sorbent sitting on a piece of quartz wool to keep it in place, it was a packed bed reactor. When it was an empty quartz tube, it was a photoreactor. Just using fancy-schmancy chemical engineering terms, but it’s not fancy. An empty quartz tube, which is transparent to UV light, now it’s a photoreactor. And when I did the sorbent experiments, I had it in a closed clamshell furnace. I had it at flue gas temperature, typically around 300 Fahrenheit. When I did syngas years later, I had it at much higher temperatures, because I wanted high-temperature sorbent. But when I did the photochemical experiments, I had to be able to irradiate the flue gas. So, I mentioned, I'm not handy, but I was fortunate, I didn't have this in grad school, but at the Department of Energy, when I started, I had a lab technician. He was able to take off the front half of my clamshell furnace, so I still had half the heating element, so I could heat the quartz tube from the rear, and I could shine a light from the front. A little germicidal UV lamp for $50 from Fisher Scientific. I could shine the light from the front, and then another couple of hundred dollars, I could measure the radiation intensity with a photodetector. I could vary the distance, so I could vary the intensity of the UV light. I essentially did another PhD thesis on photochemical removal of mercury from simulated flue gases. I published several papers on that. We patented that (our GP-254 Process) and we licensed that to a small company in New Hampshire, and that was very gratifying. They took it to larger pilot scales. I did this over twenty years ago; there are still companies and researchers that are looking at our UV method, most recently in Canada and China. I'm very excited when I see that, because what started as an accident for me, but I documented it, and I pursued it as far as I could- it’s still causing mischief around the world. So, I'm gratified about that.
Evan, I want to ask sort of a broad question that gets both from your postdoc into your transfer to working for NETL as a full-time federal employee, and that’s one of mandates. What do you see as the mandates coming from the Department of Energy that serve as the driver of your research, both in terms of the public health impact, economic considerations with regard to energy efficiency, and more recently perhaps, the need to look at energy with climate change and carbon emissions mitigation in mind?
Yes, and you hit one of the nails on the head. When I started, all the research I was doing was on mercury. And for a long time, and even to this present day, I focus on the trace and minor elements in coal. But a large focus of NETL has become carbon dioxide capture, removal, and sequestration, and even more recently, to try to make useful products out of the CO2. Because they know that that’s going to be key if we're going to continue to use coal on a massive scale for making our electricity. So yes, that’s one of the mandates, is to minimize the greenhouse gas impact of the CO2 from the coal combustion flue gas. Another one, our lab in Pittsburgh and really all of NETL is historically a coal research lab. The Morgantown lab, I mentioned, was historically a gasification lab. The Pittsburgh lab is historically a combustion lab. And more recently, approximately fifteen years ago, we have a small lab now in Albany, Oregon, they're historically a metallurgy lab. But they merged with us in 2005. But historically, we're a coal research lab. But if you look on our website, I believe we're called the fossil energy, we're the fossil energy. So, it has broadened, which is good, it has broadened over the years. Also, natural gas and petroleum, which I'm very excited about (laughter). But I think our mission is ultimately to utilize the abundant domestic coal. You know, the United States is Saudi Arabia, Iran, Iraq, Venezuela, Russia combined; the way they produce or possess petroleum, that’s what the U.S. is to coal, combined. We have by far the largest coal reserves in the world, by far. USGS and DOE estimate at least a 250- to 300-year supply, certainly at the current rate of consumption. Easily. More than 250 or 300 years. But the challenge is always, yes, it comes from the ground. I mentioned it’s from the decomposition of ancient forest and plant matter over millions and hundreds of millions of years. And during that time, there’s small contaminants native to the biomass, but the real contaminants are from the sediment and the Earth’s crust and the waters and volcanic ash that it made contact over millions and hundreds of millions of years. And because the coal is this complex matrix with the mineral oxides, the ash, and these trace and minor elements, it’s always a challenge to utilize the coal, which is good for the domestic economy. Cheap electricity is baked into the price of everything. Our rents, our monthly budgets for our homes, our offices. And now we want to use electricity for our automobiles. It’s baked into the price of a lot of things. So you want cheap electricity. That’s always good, excellent for the domestic U.S. economy. But you want to do it in an environmentally responsible manner. You don’t want to poison your own citizens in getting this cheap electricity. So that’s always the challenge, to be able to generate the energy cheaply, affordably, domestically, but also to do it in the cleanest possible manner. And we can remove, we've already done it for sulfur oxide, nitrogen oxide, particulates, and now the mercury. We’ve shown we can do that at near one hundred percent and not bankrupt anybody. But the CO2 is a bigger challenge because that’s the primary product of combustion. You know, carbon plus oxygen from the air makes carbon dioxide plus heat. That’s the basis for the coal-burning power plant. When you burn a billion tons of coal per year, that’s about two and a half billion tons of carbon dioxide. What the heck are you going to do to capture that? And there’s a lot of old methods for capturing the carbon dioxide, acid-base reactions, employing scrubber solutions just like they do for the sulfur oxides, you could do that, for example with aqueous ammonia. You could use alkaline sorbents like lime. You could use membranes. And I've been involved in some of that research. One of my first postdocs was a student from the University of Pittsburgh. He became very famous. He ended up starting his own company. He now has his own company that focuses on preventing corrosion. So, there’s a lot of known methods for removing the CO2, but the sheer volume, it’s the major product of combustion, that’s gonna- we know from back-of-the-envelope calculations, if you're going to remove most of the CO2 from a coal-burning power plant, you're probably going to double the price of electricity. So that’s a big challenge. So how to remove the CO2 cheaply, and then what the heck do you do with the CO2? And I was involved in some of that early research. NETL, we published a literature survey on CO2 capture and sequestration-that has been cited over 600 times. I'll send you that paper. It’s very unsatisfying, one of the major uses that’s proposed is just to put it in a saline aquifer and hope that it stays there and doesn't come back out to the atmosphere for 10,000 years. You went through all this expense, you doubled the price of electricity; it’s very unsatisfying, technically- yes, you got it out, you're not emitting it to the environment, it won’t contribute to greenhouse global warming, but you went to all this expense, and you're just dumping it into the ground for no good use. So, over the last twenty years, there has been a lot of effort to try to use that CO2 for enhanced oil recovery, where at least you're getting a good use out of it, and hopefully the CO2 is still staying in the ground. And then even more recently, to try to make products from the CO2, to try to make organic chemicals or plastics from the CO2. You can do it, but it’s typically not economically viable. So, that’s a current area of research. Often times, they invoke “free energy-” you know, like from solar or wind, to try to convert the stable CO2, CO2 is a stable molecule, to try to convert it into something else. So this is an active area of research at NETL right now, trying to make products from CO2, and also to try to drive the cost down. Because we know there’s a lot of ways of removing the CO2 from the flue gas, alkaline scrubbers like aqueous ammonia, alkaline sorbents or membranes. But how to do it in the cheapest possible membranes, the membrane, I always say, is a beautiful dream. I wrote the membrane section in the literature review, and I did a little bit of membrane work for my master’s thesis. A membrane, if it really works, is a dream solution. There’s no moving parts. If it has good selectivity and permeability, you could run it hopefully for months and years and do it cost-effectively. You don’t need chemicals. But in reality, membranes are often just a beautiful dream. Because in order to make them permeable, you want them to be thin. They often leak, with pinholes- the fabrication is an issue. And then a real flue gas has particles- even a clean flue gas that went through the pollution control devices, where you remove almost one hundred percent of the SOx, NOx, mercury, particulates, you still have residual small amount of entrained, nothing is one hundred percent, small amount of entrained particulates. Certainly, small amounts of SOx and NOx. And if you have a polymer membrane, they may be poisoned by these things. Particulates over time can blind the membrane. They physically block- you know, just like a filter, they form a filter cake. They can erode the membrane. If it’s thin, it can leak. So, the real-world challenge is- in the lab, you can make these beautiful membranes, and I helped start some of this research twenty years ago. But the reality is, in the real world, these membranes are often- even the cleanest flue gas is a challenging condition to try to remove the CO2. But that’s an active area of research- the membranes, and also converting the CO2 to useful products. And what I'm more directly involved in is the coal itself, these trace elements. We're still interested in these trace hazardous elements like the mercury, arsenic, selenium, cadmium, phosphorus, antimony, sulfur, halogens. We're still interested in those, but in recent years, we've been interested in some that have economic value, like the lanthanides, the rare earths, the cobalt, the gallium, the vanadium, lithium. Because when you're burning these enormous amounts of coal, you're making a lot of coal ash, and often the coal ash, a lot of it is unfortunately landfilled. Thankfully, over half of it is reused—half of the ash is used for making concrete and cement, which is a big success story. DOE has been promoting this for over thirty years. But very roughly half of it isn’t reused, and it’s in essentially ash ponds and ash impoundments. And from old power plants, there’s a lot of legacy ash ponds and ash impoundments. If we could do something useful with these, that would be a tremendous success story for the environment, for DOE, and for coal. Because if you can get all the value out of the coal, you can make it more economic. You know, coal is very cheap. I mentioned we have coal coming out of our ears in the U.S. But if we can get economic value, not only the heating value for making electricity, but if we can get some of the value out of the ash, not only the ash that’s used, a lot of it is used for making concrete and cement, but if we could use all of it to try to get some valuable elements, or to try to remediate some of these ash ponds and ash impoundments, that would be a great success story. So just recently in the last few months I started a new area of research where we're trying to get some value out of the ash impoundments to see if we can get- besides the current use, where we use some of that ash for the concrete and cement, if we could do other things with that material as well.
Evan, the term “clean coal,” it’s really a political term. It’s not a scientific term. But from your perspective, do you understand the goal of achieving a clean coal technology both as mitigating carbon emissions and making the combustion more safe?
Well, yeah. I mean, yeah, yes. Politicians may use the term “clean coal,” and that might mean something different to the scientist or the engineer or to the public. They all might have different- the public might just be concerned if they see black plumes or cloudy plumes. That’s what they might be most concerned of (laughter). Even though in reality, and at a very modern power plant, that’s mostly moisture. That’s not soot, and it’s not nitrogen or sulfur oxide. But they mean different things to different people. But I've always thought if we could drive toward as close as technically and economically feasible toward one hundred percent removal, certainly of the major pollutants, which are the SOx, NOx, the particulates, those are the major pollutants but then when you get to the minor and secondary pollutants like the mercury, which we now essentially have mandated near one hundred percent removal, that’s a great success story. But if you further go- certainly, the greenhouse gas, the CO2, it’s not a pollutant in the traditional sense, but certainly is a greenhouse gas. Even natural gas, which is very clean compared to coal, methane is an even more powerful greenhouse gas than CO2. And in the production and the drilling, the transportation and the production and the use of the methane, there’s unfortunately leaks. And because methane is about one hundred times more powerful greenhouse gas than CO2, even using a much cleaner fuel like natural gas, you may inadvertently be putting some powerful and copious amounts of greenhouse gas, methane, into the environment. So that’s something that I think deserves further research. So yeah, there’s never a shortage of research topics with fossil fuels, coal or natural gas or petroleum. Because they’re such complex matrices, and the way that we use them, we generate all these different streams—the flue gas, the syngas, the flue gas from the natural gas combustion. And even the natural gas processing, we have to remove the mercury, the moisture, the particulates, the hydrogen sulfide. Even a simple clean fuel like natural gas, there’s quite a bit of processing that goes on. And certainly a lot more with petroleum. You know, you could study the petroleum refinery for thousands of lifetimes, because it’s such a complex starting material. And even though a lot of it, the guts of it is the distillation, you could study that for a lifetime. So, there’s never (laughter) a shortage of research topics and environmental research topics when using fossil fuels. We're not going to be using fossil fuels forever. I envision probably for the next fifty to one hundred years, we'll still be using a lot of fossil fuels, certainly around the world, and I would say at least for the next fifty years in the United States. But we're not going to be using them forever. Eventually, we're gonna run out of easily accessible fossil fuels, it’s a finite resource. Or even though there’s a tremendous amount of fossil fuels in the ground, eventually they become less economic to extract as they're deeper and in more forbidding locations. So, but certainly for the next fifty years, I’d say there’s a lot of interesting and important research that could be done to allow us to use the abundant coal, natural gas, and petroleum. And a more recent phenomenon. We thought we were running out of natural gas and petroleum in the U.S. until about fifteen years ago. But with the advent of the fracking, we found we had plenty of natural gas and petroleum. I don’t say that we have hundreds of years like we do in the coal, but the estimates I've seen, we probably have at least a good fifty years of petroleum and natural gas, economically and relatively easy to extract. So if we're going to use it, we have to use it in the cleanest manner, which means we have to be able to produce it in a clean manner- that the fracking is done in a responsible manner, and that also the ultimate use, be it at the refinery, the natural gas processing, and the natural gas combustion, and hopefully one day, natural gas conversion to value-added chemicals like ethane and propane and plastics, directly from the methane, and the coal, there’s essentially still an infinite amount of research to, you know, the pollution control. There’s research that I helped start it a couple years ago to make value-add products from the coal. You know, in the U.S. most of the coal is burned to make electricity. But a small amount of it is used for steel manufacture. A small amount of it is used for exports. And a small amount of it is used for making coal tars. That's a local company in Pittsburgh, Koppers, that they use to preserve wood and to make- they also use to make electrodes for the aluminum and the metals industry. But if we could do other things, we can make graphite from coal. We can make nanocarbons from coal. There’s local companies sponsored by the Department of Energy that are making essentially carbon bricks from coal for building houses and backyard decks. If we could do some of those things, I’d say that would be a success story, because we're diversifying the use of the coal from just burning it to make electricity. So, there is a lot of research that’s just started at the DOE to try to make other products from coal besides just burning it to make electricity or gasifying it just to make syngas. And one old one is to make activated carbon. That’s really an old product that’s still made in the U.S. They make activated carbon from coal. Not food-grade activated carbon, but industrial-grade activated carbon. And that’s done by gasification. Through the carbon steam reaction, the coal plus water at high temperatures and pressure, you'll chew the coal up on a microscopic level. You have the carbon steam reaction; carbon plus water makes carbon monoxide plus hydrogen. You can recover that syngas and do things with it, but the remaining solid is like a Swiss cheese that has internal porosity. That’s the high-surface-area activated carbon. That’s an old technology. They use domestic coal to make activated carbon. That’s a few-billion-dollar-a-year domestic industry. But it breaks my heart—you know, the major use for the coal over fifty and one hundred years has been burning to make electricity. But in the last approximately five years, it has been going down. I mentioned that the peak around 2008, 2010, we were burning about a billion tons of coal per year to make fifty percent of our electricity. And for about a twenty-five-year period- I think I sent you an extended abstract from 1990 through about 2014, very roughly plus or minus one hundred million tons, we were producing and burning about a billion tons of coal per year. But over the last five, six years, trends have accelerated. We're not building new coal-burning power plants in the U.S. What you mentioned, the concern about the greenhouse gas, CO2, and looming regulation, potential regulation with CO2, especially with the prior administration, and then also, what I mentioned a few minutes ago, now that we've discovered all this new natural gas, I think a lot of the electric utilities have come to the conclusion that they’d have less grief from the regulatory bodies if they burn natural gas to make electricity than burn coal. Even if they're sitting- historically, a lot of these power plants are situated right near the mine. They literally shuttle the coal from the mine to the power plant on short rail tracks, and it’s very economical to make the electricity. But because of the concerns about the environment and especially the CO2 and the recent discovery of abundant natural gas, I don’t think it’s one hundred years- not a geologist; I'm a chemical engineer, my best guess is it’s twenty to fifty years of abundant natural gas. And it’s a beautiful thing. As I mentioned, cheap electricity is very important for the domestic economy. But it’s competing with the home heating and the home cooking. That’s always a big use for the natural gas. And the chemical industry uses natural gas, and the chemical industry always has dreams that they can directly convert the methane to things like ethane. They can indirectly do it through gasification and pyrolysis, but it’s expensive to make ethane and ethene from methane and use that to make plastics. But if you could do it directly, catalytically, which has been a big subject in the catalysis literature since 1982, that was part of my thesis, Keller and Bhasan, you'd have a multi-billion-dollar invention. And DOE is sponsoring research, I have a small project right now, where we're trying to come up with a catalyst or a method to directly convert the methane from the natural gas to ethane and more-what we really want is ethene, because the ethene is more directly used to make the polyethylene. So, that’s an area of research for the natural gas. Let me think what else. Yeah. So, I would say-so, oh, I mentioned, yeah, that we're not burning a billion tons of- since about 2014, 2015, the trends have been down. Over the last five years, we've gone from about a billion tons, which was for twenty-five years, now the most recent projection, DOE has a sister agency called the EIA, Energy Information Agency. It’s a very nice agency. It’s small; they have a few economists and scientists. But they publish wonderful statistics, weekly, monthly, and annually, how much coal we produce, how much coal we burn, how much petroleum and natural gas we produce each week, month, and year, statewide, nationwide. And those statistics show that for 2020, they're estimating we're only going to produce and burn roughly a half a billion- 500 million tons. Part of it is the economy with the COVID and the recession. But this trend has been going on for about the last five years. We had that twenty-five-year period where we were roughly at a plateau of a billion, but since about 2014, 2015, we've been in a decline. And I would say recently an accelerated decline, because a lot of these coal-burning power plants are fifty, sixty, seventy years old. They're really not economical to run. You know, they can keep running, but they're not really economical to keep running. And because of the concern about CO2 regulation and now that we have plentiful natural gas, at least right now and probably the next ten, twenty years- I don’t know about thirty or fifty or one hundred years, but probably in the next ten, twenty years, they're finding it easier just to build natural gas burning power plants. So, we had fifty percent of our electricity from coal as recently as about 2008. Now, we're down to about twenty percent of our electricity. And the trend has been going down. But what’s taking up the slack has been natural gas. That used to be about twenty percent of our electricity; now it’s over forty percent of our electricity is from natural gas. And part of the remainder is nuclear. That’s always about twenty percent. Because we don’t typically build nuclear power plants, but the ones that they have, they try to keep them running as long as possible. That’s roughly eighteen or twenty percent, so that’s sixty, eighty. That last twenty percent that’s very interesting- there’s a very small amount from oil, but renewables have been coming up over the last ten years. Wind, and solar. But they started from such a small level. But that has been growing, and that’s an interesting and growing area, is the renewable- the solar generation of electricity. And there’s actually a sister national lab, NREL, that does research on that.
Evan, what have been some of the most important collaborations, both institutionally and personally, within and beyond the federal government, for you, over the course of your career?
Well, since about 2008 or 2009, I've been an adjunct at the University of Pittsburgh. I enjoy that very much. Just I mentioned that my original dream was to be a professor, so I get to get some of that out of my system. I have to get permission to teach the class, and I typically teach it at night. And this might not be the ideal way, but the way I've been doing it, so that there’s no conflict and my management approves it, is I'll do it one day a week from 5:00 or 6:00 in the evening until 9:00 at night (laughter). Which is a little bit of a marathon, but I enjoy that very much. It makes me feel young again because I get to interact with young students. And I get to wave my arms, jump around, try to impart the excitement of the petroleum refinery or the natural gas processing or the catalyst or the sorbent. I enjoy that. I enjoyed over the years when we licensed some of our technology. We licensed our crude activated carbon that we could make at the power plant. We call that our thief carbon (Thief Process). We licensed that to several companies. One of them was MoboTec. And they demonstrated this at Canadian power plants several years ago. We licensed the patent to them. We won the R&D 100 Award with them, which was very exciting. We published some papers. That was exciting. Our UV technology (GP-254 Process), I published several papers on that, and we patented the technology. We licensed that to a little company in New Hampshire called Powerspan, which I think recently went out of business. But they demonstrated it, I would say, at large bench scale, small pilot scale. And then on their own, other- because I published on this, other companies and countries demonstrated the technology. The Canadian government has an energy research agency, Canmet. They did it at I would say pilot scale successfully, and they published on it. A small group at the University of Florida published some papers on it. Up until like the 2020, I saw the Chinese government this year published a paper on it. They did it at I would say pilot scale. So that has been very exciting. And then, you know, our syngas sorbents, we published on our high-temperature syngas sorbent that I mentioned was inspired from my undergraduate analytical chemistry lab, the graphite tube atomic absorption, where in the literature they used the noble metal salts to promote the graphite tube to retain the volatile hydride-forming elements, arsenic, selenium, mercury, up to the 400-degree drying and pyrolysis step. I published many papers, more than a dozen papers, on that, and we have several patents on that. We licensed that to Johnson Matthey. That’s probably our most satisfying commercial collaboration. Because Johnson Matthey, those other licenses were with small companies. MoboTec and Powerspan, you know, they did a nice job, they took it as far as they could, but they're very tiny companies. They didn't have the resources to fully commercialize the technology. They showed that it technically could work at large scale, we published some papers with them, but they didn't have the resources to take it all the way and fully commercialize it. But Johnson Matthey is an old, large company. They have the resources and the dedication to the basic science. Their headquarters are in the U.K. They have domestic- we were able to license it to them, because they also have domestic operations in the U.S. and around the world. They've been doing research with us formally and informally for about fourteen or fifteen years. They helped arrange with us and the Department of Energy sixteen pilot-scale tests with a ten-pound bed of palladium on aluminum beads, in slipstreams of real syngas, at real syngas temperature, dirty syngas, for a month at a time, showing that it removes one hundred percent of the mercury, arsenic, and selenium. I don’t believe they've sold it, but they have the technology. We published with them. We showed that it works. And they have the resources. They know they have a technology. We can refine it, use lower and lower loadings of palladium. We started with ten and twenty percent palladium on alumina. Our most recent experiments with them, collaboratively, have been one percent and two percent palladium on alumina. And we've even looked at other metals, because palladium is expensive. But what people don’t realize is you can use an expensive sorbent or catalyst as long as you ultimately recover it. People don’t realize in the back of their automobile, this is another Johnson Matthey product, is the three-way catalyst, which is typically platinum or palladium as well as rhodium. Those are very expensive, but it sits in the back of your car in the exhaust for ten or fifteen years. And you don’t throw it out at the end; it goes to a recycler and they recover most of the precious metal. And the same thing with our sorbent. We don’t throw these away like you might do with an activated carbon. We regenerate these used sorbents, and when we can’t regenerate them anymore, they go back to Johnson Matthey and they recover the precious metal. As a matter of fact, our experiments over the last fifteen years with Johnson Matthey is they took the (laughter) original palladium beads that we used in the mid or late 2008, 2009, and they regenerated them, and we used them again and again, over the last twenty years, at the pilot gasifier in Wilsonville, Alabama. As long as you can ultimately recover the palladium or whatever the noble metal is, you can use an expensive material, either as a catalyst or a sorbent. You just can’t throw it away. So that was very gratifying. And we've tried to discover non-noble metals that will do a similar job, and we've published on that as well. So I would say those are the most gratifying collaborations. Being able to teach the courses at the University of Pittsburgh, being on thesis committees, I always find that enjoyable. Being a mentor either for postdocs or for summer students through our Mickey Leland Energy Fellowship, which is a beautiful program, I always enjoy that. I get to get some of the teaching bug out of me. I enjoy that. And then also I didn't mention- yeah, and our licenses with our commercial partners, especially Johnson Matthey, have been very gratifying. But also, we get to do the- we have often tours that come to our lab. When they send the tours to my lab, I enjoy that. I get to be a little bit of a ham and show our tubes and our mercury- our mercury permeation tubes and our quartz tubes and our UV lamps and our different samples of coal. And I also enjoy- we have an education outreach mission. We sponsor the Science Bowl every year. And I get to be Alex Trebek once a year. Where we have a high school and a junior high school Science Bowl. And it’s a quiz on a weekend at the local community college. We're going to do it remotely this year because of COVID. But I get to be Alex Trebek. I get to read the questions (laughter). I get to be the moderator and judge. You know, if it’s close enough to the answer. And I try to console the losing teams. I tell them, “Forty and fifty years ago, no one’s going to remember whether you won or lost the local Southwest PA Science Bowl.” I tell them from my experience, "I was the captain of the math team, I had my mighty math muscles. No one cares forty or fifty years whether we beat Sheepshead Bay High School or the local high school.” I said, “The thing is that you're interested in math and science, and that you're passionate about it, and you're thinking about doing that as a career. That’s what’s important.” I try to give them a consolation speech, you know, from the heart, that- “Don’t worry whether you won or lost. Do your best but don’t worry whether you-” Some of them are so hypercompetitive, they almost break the buzzer, and they get very distraught (laughter). I look at him and I go, “I have a PhD. You're recalling facts off the top of your head. You're doing it quickly.” I said, “You're amazing.” “Win or lose,” I say, “you’re amazing.” I said, “Don’t worry about win or lose” (laughter). So, I enjoy doing that as well, and I've done that for twenty-five years.
Evan, what’s a great example that can illustrate how NETL provides you with an ideal environment, both in terms of the instrumentation and the laboratory, both in terms of the intellectual collaboration, what’s a great example of how NETL is really the ideal place for you to conduct the research that’s most compelling and interesting to you?
Well, I mean, they give us- we have to have it tied to fossil energy, typically coal, and more recently natural gas and petroleum. So, you know, there is that limitation. But I say, under that broad umbrella of fossil energy, you can do virtually any research that you can imagine, under that umbrella. Honestly, you can. Kinetics, catalysis, sorbents, pollution control. If you're interested more in the mechanical engineering aspects, the electricity generation, the combustion process. Anything you can imagine. You know, if you're interested in the ash, recovery of valuable metals, or remediation of these ash sites. Or if you want to make carbons from coal. I think I have a slide somewhere- I'll send it to you (laughter)- under the umbrella of fossil energy, even just coal, you can do almost any energy you imagine. And because they give us a fair amount of freedom—as long as we're productive, they give us a fair amount of freedom- yeah, it is very gratifying. You're limited mostly by your imagination. Because a lot of the starting materials, there’s no problem getting coal samples, or ash samples, or making natural gas, or getting petroleum samples. You're mostly limited by your imagination, and what you'd like to do with these materials.
Evan, just to bring the discussion up to the current day, what are some of the key projects that you're working on currently?
Right now, for most of my twenty-four, twenty-five years at the Department of Energy, I focused on the trace and minor elements, primarily mercury. But more recently, I've focused on some of the trace and minor species that have economic value, the rare earths. I led that effort for four years, and I was involved in that effort for over six years, and that was very gratifying. But even more recently, I'm going back to some of my roots. My PhD thesis was on hydrocarbon oxidations and hydrocarbon catalysis. So, I have a small project that I proposed with a collaborator, where we're trying to convert the methane with catalysts to ethane and ethene to try to have a cheaper basis of making plastics in the United States from abundant domestic natural gas. I have a small project on that. And I'm leading a new effort also on the ash impoundments and the ash ponds, on trying to make better use- you know, yes, we use some of the ash, the fly ash that we produce, from the coal combustion, to make concrete and cement, which is a great success story. But we don’t use one hundred percent of it. Plus, we have these large impoundments, over 300 of them, scattered across the U.S. If we could do something useful with that material, that would be a tremendous success story. So (laughter), over the last- really starting with the COVID, starting with March, I was assigned a new effort to start a new research effort on- they're calling it emissions control, but it’s really the ash impoundments and the ash ponds, trying to come up with good uses on how to use that voluminous material. There’s probably several billion tons, very crudely probably five billion tons, of bottom ash and fly ash in impoundments scattered across the U.S. (laughter). And you can seal them up and seal them up safely, but just like injecting the CO2 in the ground and getting no value from it is not satisfying, sealing up those ash impoundments to protect the environment, which is a good thing, but not getting any value out of it, is not satisfying. So, if we can come up with some good use for this voluminous material, which we're trying to come up with right now, that’s exciting. And yeah, there are some things that are very interesting. There are interesting not only the toxic elements which we know about, you know, the mercury, arsenic, selenium that are in those materials but there’s also the rare earths, lithium, gallium, germanium, cobalt, iron, plenty of aluminum. Aluminum is a major constituent of ash. There’s a lot of valuable elements in there. But even beyond that, we know that there’s unburned carbon in this ash. That could be an interesting material to recover, to make activated carbons or even graphite or graphene. So, we're trying to use our imagination and see if there’s anything practical we could do with this material. And if we could use some of that material for concrete and cement, that would be a win as well. Because typically, you use the fresh fly ash right from the power plant. You don’t typically use the impounded fly ash. So, if we could use some of that material for the concrete, that would be a success story as well. So, we're trying to use our imagination and literature search right now to try to come up with good ways to use the voluminous material that are in these ash impoundments scattered across the U.S. That’s something that I'm working on right now as well.
Evan, for the last part of our talk, I’d like to ask a broadly retrospective question about your career, and then one sort of looking forward. So, looking over the course of your career so far, given that so much of your research has such a clear and important societal impact, both as a concerned citizen and as a scientist, is there any one research project that you've been involved in that gives you the most satisfaction or pride?
Well, I would say the mercury research, it took a long time. I mentioned that EPA announced its intention in 1990 to regulate the mercury emissions from the coal-burning power plants. And the motivation was twofold, that they took care of the big mercury polluters just earlier, the incinerators, medical and municipal and hazardous waste incinerators. So, they were next on the list. But then also, the concern with mercury is it’s a neurotoxin. And because elemental mercury is a semi-noble metal, it can travel across the globe. Emissions from China- China is burning more and more coal, while we're burning less and less. Emissions from China have been shown, they can go across the Pacific, and they make it to the western U.S. They can make it across the whole U.S. That the residence time of mercury in the atmosphere could be as much as three months, and it could circle the globe several times. Eventually it becomes oxidized, and once it’s oxidized, that’s when it becomes- it causes mischief. Once it’s oxidized, it has water solubility. It can get into the water streams, the rivers, the oceans. And then they become methylated, the microorganisms, the plankton, the algae, they can methylate. And once it gets into the small organisms, then it’s a problem, because then it builds up in the food chain. It ends up building up sometimes to PPM levels in the large predator fish at the top of the food chain, swordfish, shark, tuna, mackerel. And that’s why EPA was concerned. They're not so concerned about a tenth of a part per million of mercury in the coal, one part per billion in the untreated flue gas. These are infinitesimal concentrations. But because they know that it can ultimately get into the food chain and build up in the large predator fish, the tuna or the shark, the swordfish, the mackerel, there’s a concern. Because it is a known neurotoxin. They worry about the effects on the fetus, with pregnant women, as well as young children. Tuna is a cheap protein staple. If you can’t feed your kids a tuna fish sandwich, or pregnant women tuna fish, that’s a problem. So, it is satisfying that, in a dark, dank lab, you know, we didn't have great facilities, but I had and have wonderful colleagues, Henry Pennline- and a nice mission, to clean up the mercury emissions associated with burning coal to make electricity. From those humble-with the most primitive mercury detector and the most primitive reactor, quartz tubes , we were able to come up with- basically our imagination and a thorough literature survey, which I say is a good way to start- my advisor, Henry Pennline, hit it on the head, start out with something easy, but very important; do a thorough literature survey, see what’s already been done, and then use your imagination and whatever technical background you have- what can be done beyond that? Using that humble beginning where I say that in retrospect, I think I did two additional PhD theses, those three years I was a postdoc, one on the sorbent, where I screened and proposed hundreds of different sorbents. It kept me busy and happy every day. I designed the sorbent experiments on the back of the pizza menu to basically take eight hours, using the quartz tube and my mercury source, the permeation tube and the atomic fluorescence detector to make my breakthrough curves. But then also the spinoff of what we found midway through, that I was getting these unwanted stains, I did a second PhD thesis, something I didn't really have a background in, but I was interested in because I always liked physical chemistry back from my undergraduate days, was the photochemical experiments. I did a second PhD thesis showing that that application of UV light could be a way of removing mercury from the power plants. So that was very gratifying, that from these humble beginnings and very little funding, you know, on the order of ten or $20,000, which was (laughter) very modest funding, I was able to develop commercial technologies for the flue gas, for the syngas. And we ended up having six patents and about nine or ten patent applications. And we had about four or five licensees. And it was very gratifying that we had at least a part in coming up with technical solutions to remove the mercury from the power plant flue gas and the coal syngas. So that was I would say the most gratifying.
And Evan, on that note, for my last question, looking to the future, thinking about the possibilities of what you'll be able to contribute to all of these macrosocial problems with regard to energy, what are you most excited about, and what is most feasible in terms of real breakthroughs on improving the viability both from an economic and a public health and a climate change perspective, with regard to using fossil fuels many decades into the future?
And I say that we will be using- I don’t say for hundreds of years, but I do say, from what I know, the estimated easy reserves that we have in the U.S. and the known issues with greenhouse gas and global warming, I do say that if we do it in an intelligent manner, we could be using fossil fuels extensively in the U.S. probably at least for the next fifty years. I don’t say hundreds of years, but easily for the next fifty years. But in order to do that, we have to show that we're diligently removing as close to one hundred percent of the pollutants as we can, and then also that we're trying to use it in new and novel and intelligent ways. There’s nothing wrong with burning the natural gas for home heating and home cooking for making electricity; that’s beautiful. But I’d say that’s the low-hanging fruit. If you could make new industries based on the natural gas, new plastics, and new chemical industries, that would be a great breakthrough. Because not only would you have new products, but you'd have new industries, new jobs. And when I teach the natural gas and the petroleum processing, I have the tongue-in-cheek “Granite equation” in one of the first slides. And I say- I'll send you the slides- the “Granite equation,” I say that coal, natural gas, and petroleum is equal to the health, wealth, and prosperity of humanity. And you know, sometimes that’s a controversial statement. But I say, if you really thinking about it, our ancestors, God bless them, they had short, brutal, terrible lives. They had short life spans. They had to live very close to where they were born. There was no mass transportation. When it was cold outside, they were cold. When it was hot outside, they were hot. It was hard to have potable, clean water. Because of plentiful coal, primarily coal, historically, but also natural gas and petroleum, we're so fortunate. We can go anywhere we want. We can control the climate. We can have air conditioning and heat. Our life spans, thankfully, are much longer. I don’t say it’s perfect. I'm not naïve. There are issues. Because these are complex matrices, they come from the Earth’s crust, especially the coal, to a lesser degree, the petroleum, and to the least degree, the natural gas-that’s always things you need to remove to make it clean. But I say that if you diligently remove as close to one hundred percent of the pollutants as you can, if you do that, then I say it’s a win/win for everybody. For the environment, for the economy, for the public health and welfare. I say, without a doubt, it’s a great win. And in order to continue using it, we need to continue- our historic mission at NETL is really pollution control. We need to continue that, but also need to come up with new uses. Because the reality at least for coal is, it’s being whittled down for generation of electricity. Which is unfortunate because we have coal coming out of our ears. If we burn it in a modern power plant, it can be done very cleanly. But the reality is, we have this abundant natural gas, which is even cleaner, so that’s what’s taking up the slack. So for the coal, if we can come up with new uses for the coal, new activated carbons, new carbon building materials, new nanocarbons, new chemicals from coal, that would be a win. If we could do more things with the coal, byproducts, which we don’t even have to mine coal, because they're in all these impoundments, that would be a win. And a similar story with the petroleum. The refinery- I say, because I have a bias toward the power plants and the gasifiers, the refinery, I say, is the second most beautiful manmade plant. You could study the refineries for hundreds of years. But they're doing it the same way that they've really been doing it for 150 years. The heart of the refinery are the two distillation columns, the atmospheric and the vacuum distillation column. If you could do some novel processing at the refinery, I don’t know what, but I think with imagination, we could do other things with the refinery also, and come up with new products from petroleum. There’s extensive pollution control at a refinery, but there’s always room-there’s certainly room for improvement for the refinery. And they don’t build new refineries in the U.S. If we could build new modern refineries in the U.S. that have legitimately near zero emissions and perhaps make even new products from the petroleum beyond the gasoline, the jet fuel, the waxes, the asphalts and whatever- if we could make new product, that would be a tremendous win for the U.S. economy. So, I always say, if we take advantage of what’s in the U.S., we have the technical know-how, we have the abundant- at least for the next fifty years, abundant fossil resources, it behooves us to use it intelligently, cleanly, and in new ways. That’s a win-win for everybody. And I show pictures in my introductory slides for natural gas and petroleum processing course that I've taught for the last three years. Yes, pollution breaks my heart, but also, it breaks my heart- I see homeless people on the streets of downtown Pittsburgh, even before the pandemic; that breaks my heart, too. And if you have new industries, and if they're done in a clean manner, that’s a win for society as well. So, I try to impart to them, you want to remove as close to one hundred percent of the pollutants as possible, you know, that’s your responsibility as a socially aware chemical engineer. You want to remove as close as possible to one hundred percent of the pollutants as humanly possible, but you also want to come up with new ways of processing the materials. Because a lot of times, we're doing it the same way we've been doing it for the past one hundred, 150 years. We're burning the coal very similar to the way we were burning it one hundred years ago. The only major difference is, thank goodness there’s a lot of pollution control on the back end. We're refining the petroleum in not too different- the historic, in 1860s in Titusville, Pennsylvania, we're not doing it too differently. There, it was a distillation column. Now, it’s distillation columns and a lot of pollution control and some refining of heavy products. But if we could do things in different manners, we could have new industries for the next fifty and one hundred years. So that’s what I try to encourage the students. And I try to keep my mind open to as well.
Well, Evan, it has been a great pleasure speaking with you today and hearing your perspective on all of these enormously important issues.
It has been a pleasure talking to you! (laughter) I bent your ear for over two hours!
And I've really enjoyed your Brooklyn accent, which I'll take as that I did my job, that I asked the kinds of questions that really got you going (laughter).
Got me excited. Thank you!