Due to coexisting of H2, CO2 and H2O with CO in hydrogen-rich gas produced from methanol reforming, the selective CO oxidation is companied with the side reactions of H2 oxidation, as well as CO or CO2 methanation and...Due to coexisting of H2, CO2 and H2O with CO in hydrogen-rich gas produced from methanol reforming, the selective CO oxidation is companied with the side reactions of H2 oxidation, as well as CO or CO2 methanation and reverse water-gas shift reaction（RWGS）. This paper investigated the effects of the above side reactions on the selective CO oxidation over a 0.5% Pt/Al2O3 monolithic catalyst. The results showed that after 50% H2 is added into the reactants, the highest CO conversion is only 98.3% at 180℃ when the feed molar ratio of O2 to CO is 1, and the corresponding outlet CO concentration is 180×10 -6 . Adding 50% H2 into the reactants accelerate CO oxidation at low temperatures; the catalyst active reaction temperature window shifts down about 40℃ . CO produced from RWGS is 80×10 -6 at 200℃ indicating that the effect of RWGS on selective CO oxidation becomes obvious at temperatures higher than 200℃. On the other side, CO or CO2 methanation does not take place even at 300℃ under current conditions and has little effects on the selective CO oxidation.展开更多
基金supported by the National Key Research and Development Program of China(2020YFB0606404)National Natural Science Foundation of China(21991092,22272195,U2003123,U1910203).
文摘Due to coexisting of H2, CO2 and H2O with CO in hydrogen-rich gas produced from methanol reforming, the selective CO oxidation is companied with the side reactions of H2 oxidation, as well as CO or CO2 methanation and reverse water-gas shift reaction（RWGS）. This paper investigated the effects of the above side reactions on the selective CO oxidation over a 0.5% Pt/Al2O3 monolithic catalyst. The results showed that after 50% H2 is added into the reactants, the highest CO conversion is only 98.3% at 180℃ when the feed molar ratio of O2 to CO is 1, and the corresponding outlet CO concentration is 180×10 -6 . Adding 50% H2 into the reactants accelerate CO oxidation at low temperatures; the catalyst active reaction temperature window shifts down about 40℃ . CO produced from RWGS is 80×10 -6 at 200℃ indicating that the effect of RWGS on selective CO oxidation becomes obvious at temperatures higher than 200℃. On the other side, CO or CO2 methanation does not take place even at 300℃ under current conditions and has little effects on the selective CO oxidation.
