(Invited) Challenges and Opportunities in the Integration of CO2 Capture and Conversion

Over the past 15 years or so, the electroreduction of CO 2 for the synthesis of intermediates for the chemical industry as well as for the synthesis of small molecule fuels has become a very active area of research. Activities span the whole value chain from electro-catalyst synthesis and characterization, to electrode and cell design and optimization, as well as studies on techno-economic feasibility and life cycle assessment of envisioned overall processes. In the vast majority of these studies, >98% pure CO 2 is being used as the feed. In reality, CO 2 feeds captured from industrial flue gasses or even those captured from air may not be close to 100% in CO 2 . This presentation will explore the integration of a nanomembrane-based CO 2 capture method with different CO 2 electrolysis approaches. The nano-membrane-based CO 2 capture is based on work by Fujikawa and Selyanchyn ( Polymer J. 2021 , 53 , 111), using polydimethylsiloxane-derived membranes that are preferentially permeable to CO 2 over nitrogen. Multistage arrangement of modules comprised of arrays of membranes allows for efficient concentration of CO 2 from air, from 420 ppm to tens of percent, using just vacuum pumps to drive the process. We explore the use of these concentrated CO 2 streams that still contain nitrogen and some oxygen as the feed in subsequent CO 2 electrolysis conversions to CO, to methane, or to other products, depending on catalyst choice. We study the effects of feed composition, catalyst chosen, and cell configuration on product speciation, conversion efficiency, etc.