Fig. 1: Scheme of the pH swing carbon capture flow system.
From: Low energy carbon capture via electrochemically induced pH swing with electrochemical rebalancing
a Schematic of the reversible PCET (proton-coupled electron transfer) reaction underwent by DSPZ (sodium (3,3′-(phenazine-2,3-diylbis(oxy))bis(propane-1-sulfonate))) in an aqueous solution. b Schematic of the Fe(CN)6 (posolyte) | DSPZ (negolyte) flow cell and full system. Blue arrows indicate gas flow direction. Adapted from ref. 18. c Process flow. TA is total alkalinity and DIC is dissolved inorganic carbon. The solid arrows refer to desired reactions in a complete carbon capture/release cycle. The carbonate formation and decomposition reactions are neglected for simplicity. The dashed arrow on the right side refers to the side reaction caused by oxygen and the dashed arrow on the left refers to reactions in the electrochemical rebalancing step.
