Lecture

Van Marum Colloquium: CO2 Electrolysis Systems for Chemical and Food Production

Prof. Feng Jiao (Washington University, St. Louis, USA)

Date: Tuesday 7 May 2024
Time: 16:00 - 17:00
Location: Gorlaeus Building
Einsteinweg 55
2333 CC Leiden
Room: DM.1.09

Abstract

Traditional chemical industry processes often rely on fossil fuels, which inevitably emit substantial quantities of CO₂. Turning CO₂ into valuable chemicals is a potential approach for sustainable chemical production. In this presentation, we will showcase our work on developing a two-step tandem CO₂ electrolysis system for acetate production. We will share our initial discovery of acetate formation in CO electroreduction on Cu catalysts. Mechanistic studies suggest that a ketene-like intermediate is the key for the formation of acetate. With further efforts in reactor engineering, we successfully developed an internally coupled purification strategy that significantly enhances acetate concentration and purity in CO electrolysis.[1] This approach employs an alkaline-stable anion exchange membrane with high ethanol permeability and a selective ethanol partial oxidation anode to regulate the CO reduction product stream.

We successfully demonstrated a stable 120-hour continuous operation of the CO electrolyzer at a current density of 200 mA cm^-2 and a full-cell potential of less than 2.3 V, consistently producing a 1.9 M acetate product stream with a purity of 97.7%. This performance is among the best reported in the literature. The ability to convert CO₂ into acetate has opened the possibility of developing an electrochemical-biological hybrid approach to produce food from CO₂, offering much higher efficiency than natural photosynthetic pathways.[2] Furthermore, we will discuss our recent efforts in scaling up CO electrolysis systems for practical applications.

Reference

S. Overa, B. Crandall, B. Shrimant, D. Tian, B. H. Ko, H. Shin, C. Bae and F. Jiao*. Enhancing acetate selectivity by coupling anodic oxidation in carbon monoxide electroreduction. Nature Catalysis 5, 738-745 (2022). 10.1038/s41929-022-00828-w
E. C. Hann, S. Overa, M. Harland-Dunaway, A. F. Narvaez, D. N. Le, M. L. Orozco-Cardenas, F. Jiao* and R. E. Jinkerson*. A hybrid inorganic-biological artificial photosynthesis system for energy-efficient food production. Nature Food 3, 461 (2022). 10.1038/s43016-022-00530-x