Pairing electrochemical CO2 reduction with glycerol oxidation: Bottlenecks today, opportunities tomorrow
Attila Kormányos, Adrienn Szirmai, Balázs Endrődi, Csaba Janáky
Abstract
One of the greatest obstacles hampering the industrial application of CO 2 electrolysis is the large cell voltage (often over 3 V), which is mainly rooted in the high redox potential and overpotential of the oxygen evolution reaction (OER) occurring at the anode. It is possible to mitigate this issue by replacing the OER with alternative processes, such as the electrochemical oxidation of small organic molecules. Although the number of examples of paired CO 2 reduction reaction (CO 2 RR)/small organic molecule oxidation is rapidly increasing, their viability has only been tested at the laboratory scale, mainly in batch cells. In this perspective, taking the glycerol oxidation reaction (GOR) as an example, the main challenges concerning the quantification of GOR products, the use of crude glycerol as a feedstock, and the integration of GOR with CO 2 RR are summarized. Finally, the most important envisioned future steps for the implementation of paired CO 2 RR/GOR electrolysis at scale are outlined.