(730j) Tandem Carbon Dioxide Electrolysis Process for Multicarbon Chemical Production

Electrochemical conversion of carbon dioxide (CO₂) using renewable electricity is an attractive approach for sustainable production of fuels and chemicals. Copper (Cu) has a unique capability of catalyzing carbon-carbon (C-C) bond formation to form high-value multi-carbon (C₂₊) products. While highly alkaline electrolytes are often used to enhance C₂₊ selectivity, the inevitable reaction of hydroxide ions with CO₂ to form undesired carbonates at the electrode-electrolyte interface disrupts the electrolysis process. This fundamental challenge can be solved by decoupling the CO₂ electrolysis into a two-step process, where CO₂ is first electrochemically reduced to carbon monoxide (CO) at neutral conditions, followed by CO electroreduction to produce C₂₊ chemicals in alkaline environments. The feasibility of two-step tandem CO₂ electrolysis has been demonstrated experimentally by Romero Cuellar and co-workers [1], who reported a total CO₂ reduction current density of 300 mA/cm² with a cumulative Faradaic efficiency of 62% towards C₂₊ products. However, the system is far from optimized when compared to standalone CO₂ and CO electrolysis technologies. In this talk, we will present the latest development of the tandem CO₂ electrolysis process for multicarbon chemical production, including the electrocatalyst design, reactor engineering, process optimization, and techno-economic analysis. Additionally, we will discuss the future opportunities for carbon dioxide utilization through tandem and hybrid processes [2].

Reference:

[1] Romero Cuellar, N.S., Scherer, C., Kaçkar, B., Eisenreich, W., Huber, C., Wiesner-Fleischer, K., Fleischer, M., and Hinrichsen, O. Two-step electrochemical reduction of CO₂ towards multi-carbon products at high current densities. J. CO₂ Util. 2020; 36: 263-275.

[2] Overa, S., Feric, T. G., Park, A. H. A.* & Jiao, F.* Tandem and Hybrid Processes for Carbon Dioxide Utilization. Joule 5, 8-13 (2021). doi: 10.1016/j.joule.2020.12.004