Influence of residual K+K+ on the catalytic performance of CuO–CeO2CuO–CeO2 catalysts in preferential oxidation of CO in excess hydrogen

Influence of residual K+K+ on the preferential oxidation of CO in excess hydrogen (PROX) over CuO–CeO2CuO–CeO2 catalysts was investigated. CuO–CeO2CuO–CeO2 catalysts were characterized by BET, ICP, XRD, UV-Raman and TPR techniques. The results showed that the existence of residual K+K+ made αα peak in TPR of CuO–CeO2CuO–CeO2 catalysts shift to higher temperatures and depressed the PROX in the absence of CO2CO2 and H2OH2O in the feed over CuO–CeO2CuO–CeO2 catalysts. However, small amount of residual K+K+ was beneficial to the catalytic performance of CuO–CeO2CuO–CeO2 catalysts in the PROX in the presence of CO2CO2 and H2OH2O in the feed. Consequently, residual K+K+ with an appropriate content was beneficial to improve the catalytic performance of CuO–CeO2CuO–CeO2 catalysts in the presence of CO2CO2 and H2OH2O.