Toward economical application of carbon capture and utilization technology with near-zero carbon emission

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.