CO2一步电化学转化技术的可行性研究

目的研究长期载人航天任务中舱室CO2电化学还原为代氢燃料CO技术。方法研究不同温度、压力下,0.5mol·L-1KHCO3水溶液中Pb电极上CO2电化学还原的行为,并进行电极反应动力学研究。结果常压下,温度为273K,电解电位-1.5V,产生的CO法拉第效率最大,为16.1%;常温下,压力为1.2MPa,电解电位-0.5V,产生的CO法拉第效率最大,为19.8%。通过动力学研究,得阴极还原生成CO的反应级数为0.34。结论载人航天器中应用电化学还原CO2为代氢燃料CO的途径是可行的。

Study on Feasibility of One-step Electrochemical Conversion of CO2

Objective To develope a technology of electrochemical reduction of CO_2 to CO in manned space cabin. Method Electrochemical reduction of CO_2 with a Pb electrode in 0.5 mol/L KHCO_3 aqueous solution was studied under different temperature and different pressure and the electrode kinetics was investigated. Result Under normal ambient pressure, the temperature of 273 K and the electric potential of -1.5 V, the faradaic efficiency of CO reached a maximum value of 16.1%. Under normal ambient temperature, the pressure of 1.2 MPa and the potential of -0.5 V, the faradaic efficiency reached the highest value of 19.8%. Kinetics analysis demonstrated that the reaction order was 0.34 for electrochemical reduction of CO_2 to CO. Conclusion It is feasible for the electrochemical reduction of CO_2 to CO to be applied in manned spacecraft.