Direct Solid Oxide Electrolysis of Carbon Dioxide

The production of carbon-based chemicals in chemical industries is heavily resting on fossil resources. The efficient usage of carbon dioxide as a substitute source of carbon enables a transformation towards sustainability in the chemical sector. Therefore, carbon dioxide is converted to carbon monoxide, which is the directly activated carbon source for follow-up reactions. This can be accomplished by electrochemical reduction in solid oxide cells. In this highlight, we investigate the process performance of the direct high-temperature electrolysis of CO₂ by current-voltage characteristics (iV) and Electrochemical Impedance Spectroscopy (EIS) experiments. The versatility of the procedure is shown by the variations of the operation parameters temperature, load, fuel utilization, feed gas ratio and flow rate. It is possible to maintain high current densities of 0.75 up to 1.5 A·cm^-2, therefore resulting in high conversion rates. Thereby, our work allows the contemplation of electrolysis for the production of carbon monoxide by diversifying from co-electrolysis and pure water electrolysis coupled with water-gas shift reaction. Therefore, the potential of the conversion of carbon dioxide to carbon monoxide via solid oxide electrolysis to be a key enabling technology for the transformation of chemical industry from fossil resources to sustainable sources of carbon is disclosed.

Foit, S.; Dittrich, L.; Duyster, T.; Vinke, I.; Eichel, R.-A.; de Haart, L.G.J. Direct Solid Oxide Electrolysis of Carbon Dioxide: Analysis of Performance and Processes. Processes 2020, 8, 1390. https://doi.org/10.3390/pr8111390

Received: 1 October 2020 / Revised: 26 October 2020 / Accepted: 26 October 2020 / Published: 31 October 2020