High-temperature furnace and cell holder developed for molten salt characterizations

Molten salt nuclear power reactors use molten salt as their primary heat transfer fluid, rather than water as in typical commercial reactor designs. The design offers advantages, including improved safety, and has seen a growing interest in its further development. As part of the U.S. Department of Energy’s Office of Basic Energy Sciences Molten Salts in Extreme Environments (MSEE) Energy Frontier Research Center, Phillips et al. developed three technologies to aid in the characterization of molten salts under envisioned reactor conditions.

The first of these devices is a spectroelectrochemical molten salt furnace capable of simultaneous optical spectroscopy and electrochemical measurements at temperatures up to 700 C. The second device – a modular, high-temperature cell holder – enables time-resolved interrogation of radiation-induced processes in molten salts. A miniaturized version of the spectroscopy furnace is the third device, designed to investigate steady-state radiation effects.

“The ability to use multiple spectroscopic techniques along with electrochemistry sequentially on the same sample is very unique,” said author William Phillips.

“We put so much time and effort into establishing these capabilities, that now that they’re in place, the science is going to snowball,” added author Gregory Horne.

Using these technologies, the MSEE team has a wide variety of experiments planned to better understand molten salts on a molecular level. Further modifications are planned to allow studies at even higher temperatures, potentially reaching 1,000 C.

“The instruments we designed are quite versatile,” said author Ruchi Gakhar. “We have expanded the capability for molten salts characterization from benchtop to synchrotron facilities.”

Source: “Design and performance of high-temperature furnace and cell holder for in situ spectroscopic, electrochemical, and radiolytic investigations of molten salts,” by William C. Phillips, Ruchi Gakhar, Gregory P. Horne, Bobby Layne, Kazuhiro Iwamatsu, Alejandro Ramos-Ballesteros, Michael R. Shaltry, Jay A. LaVerne, Simon M. Pimblott, and James F. Wishart, Review of Scientific Instruments (2020). The article can be accessed at https://doi.org/10.1063/1.5140463 .