Electrolytic conversion of carbon capture solutions containing carbonic anhydrase.

The electrolysis of carbon capture solutions bypasses energy-intensive CO recovery steps that are often required to convert CO into value-added products. We report herein an electrochemical flow reactor that converts carbon capture solutions containing carbonic anhydrase enzymes into carbon-based products. Carbonic anhydrase enzymes benefit CO capture by increasing the rate of reaction between CO and weakly alkaline solutions by 20-fold. In this study, we reduced CO-enriched bicarbonate solutions containing carbonic anhydrase ("enzymatic CO capture solutions") into CO at current densities of 100 mA cm. This result demonstrated how to electrolyse enzymatic CO capture solutions, but the selectivity for CO production was two-thirds less than bicarbonate solutions without carbonic anhydrase. This reduction in performance occurred because carbonic anhydrase deactivated the catalyst surface. A carbon microporous layer was found to suppress this deactivation.