一氧化碳(CO)催化氧化反应因在实际生活中应用广泛而受到人们普遍关注,如激光器中微量CO的消除、封闭体系中CO的消除、汽车尾气净化以及质子交换膜燃料电池中少量CO的消除等。本文总结了近年来CO低温催化氧化研究进展,包括催化剂及其制备方法、CO氧化反应机理以及不同环境气氛对催化剂CO低温氧化性能的影响。催化剂的制备方法主要包括传统浸渍法、共沉淀法、沉积-沉淀法、溶胶-凝胶法、离子交换法、化学气相沉积法、溶剂化金属原子浸渍法等。催化剂可分为贵金属催化剂、非贵金属催化剂、以分子筛为载体的催化剂和合金催化剂等。CO氧化反应机理方面的相关报道较多,人们针对不同催化剂体系提出了各种假设。不同环境气氛对催化剂CO低温氧化性能的影响主要分为H2O、CO2、H2和其他气氛等4部分进行描述。最后对该领域的发展前景进行了展望。
The catalytic oxidation of carbon monoxide (CO) at low temperature has attracted considerable attention because of its wide applications in exhaust abatement for CO2 lasers, trace CO removal in enclosed atmospheres, automotive emission control, and CO preferential oxidation (PROX) for proton exchange membrane fuel cells (PEMFC). Progress in low-temperature catalytic oxidation of CO is summarized. Catalysts and their preparation methods, reaction mechanisms of CO oxidation and the effects of different coexisted atmospheres on the catalytic performance of the catalysts are reviewed. The preparation methods include impregnation, eoprecipitation, deposition-precipitation, sol-gel, ion exchange, chemical vapor deposition, electrochemistry deposition, inert gases condensation, solvated metal atom impregnation and so on. The catalysts for low-temperature CO oxidation consist of noble metal catalysts, non-noble metal catalysts, catalysts supported on molecular sieves and alloy catalysts. The mechanisms of low-temperature CO oxidation are reported by many researchers, and various hypothesisses are put forward on different catalysts. The effects of H2O, CO2, H2 and many other coreactants on the performance of low-temperature CO oxidation are expatiated on. The prospects for this field are brought forward.