We present a study on the electrochemical behavior of magnesium hydroxide (MgOH + ) reduction on a tungsten (W) cathode in molten chloride salt (MgCl 2 -KCl-NaCl) across the temperature range of 475 °C–525 °C. MgOH + , which forms within the salt upon exposure to moisture, is a leading cause of corrosion. Corrosion is a major barrier to deployment of chloride salts across a number of applications, including concentrating solar power plants and nuclear power plants. While pre-purification protocols have been developed to ensure MgOH + is removed from molten chloride salts prior to deployment, MgOH + forms in situ during operation of chloride-salt based plants. Thus, methods for continuous purification during plant operation are needed. Continuous electrochemical purification via electrolysis using a Mg anode and W cathode has been proposed, but little has been done to assess scalability. Here, we assess fundamental properties of electrochemical removal of MgOH + to enable future scale up of this method.
Witteman, Liam, Rippy, Kerry, Taylor, Patrick, et al., "Continuous Purification of Molten Chloride Salt: Electrochemical Behavior of MgOHCl Reduction," Journal of the Electrochemical Society 170, no. 6 (2023), https://doi.org/10.1149/1945-7111/acd878
@article{osti_1983458,
author = {Witteman, Liam and Rippy, Kerry and Taylor, Patrick and Vidal, Judith},
title = {Continuous Purification of Molten Chloride Salt: Electrochemical Behavior of MgOHCl Reduction},
annote = { We present a study on the electrochemical behavior of magnesium hydroxide (MgOH + ) reduction on a tungsten (W) cathode in molten chloride salt (MgCl 2 -KCl-NaCl) across the temperature range of 475 °C–525 °C. MgOH + , which forms within the salt upon exposure to moisture, is a leading cause of corrosion. Corrosion is a major barrier to deployment of chloride salts across a number of applications, including concentrating solar power plants and nuclear power plants. While pre-purification protocols have been developed to ensure MgOH + is removed from molten chloride salts prior to deployment, MgOH + forms in situ during operation of chloride-salt based plants. Thus, methods for continuous purification during plant operation are needed. Continuous electrochemical purification via electrolysis using a Mg anode and W cathode has been proposed, but little has been done to assess scalability. Here, we assess fundamental properties of electrochemical removal of MgOH + to enable future scale up of this method. },
doi = {10.1149/1945-7111/acd878},
url = {https://www.osti.gov/biblio/1983458},
journal = {Journal of the Electrochemical Society},
issn = {ISSN 0013-4651},
number = {6},
volume = {170},
place = {United States},
publisher = {The Electrochemical Society},
year = {2023},
month = {06}}
SOLARPACES 2018: International Conference on Concentrating Solar Power and Chemical Energy Systems, AIP Conference Proceedingshttps://doi.org/10.1063/1.5117729