Toward Electrochemical Marine Carbon Removal Using Immobilized Proton Carriers

The use of renewable electricity to drive large-scale electrochemical CO2 removal and concentration from point sources, air, and seawater is receiving considerable interest as one strategy for mitigating climate change. Yet, the low concentration of CO2 in air makes rapid and energy-efficient CO2 capture challenging. Understanding and optimizing the energetic cost of CO2 separation at commercially relevant throughput is a prerequisite for designing practical carbon removal processes. In this talk, I will review a new process for pH-swing-driven removal of marine carbon using organic proton carriers conformally attached to the internal surface area of a porous conducting substrate. These electrodes effect a reversible pH swing in seawater upon redox cycling in a flow cell. If deployed at scale, this system has the potential to meaningfully contribute to atmospheric CO2 mitigation. I will describe our past and ongoing efforts at establishing the feasibility of this concept using experiments and modeling, and a recent attempt at commercialization through a start-up company.