Abstract
Carbon capture and utilization technology has been studied for its practical ability to reduce CO(2) emissions and enable economical chemical production. The main challenge of this technology is that a large amount of thermal energy must be provided to supply high-purity CO(2) and purify the product. Herein, we propose a new concept called reaction swing absorption, which produces synthesis gas (syngas) with net-zero CO(2) emission through direct electrochemical CO(2) reduction in a newly proposed amine solution, triethylamine. Experimental investigations show high CO(2) absorption rates (>84%) of triethylamine from low CO(2) concentrated flue gas. In addition, the CO Faradaic efficiency in a triethylamine supplied membrane electrode assembly electrolyzer is approximately 30% (@-200 mA cm(-2)), twice higher than those in conventional alkanolamine solvents. Based on the experimental results and rigorous process modeling, we reveal that reaction swing absorption produces high pressure syngas at a reasonable cost with negligible CO(2) emissions. This system provides a fundamental solution for the CO(2) crossover and low system stability of electrochemical CO(2) reduction.