Reforming of Methane over Ceria and Perovskite-Based Catalysts

摘要

The influence of the nature of the support on the activity of rhodium based catalysts in thecatalytic reforming of methane has been studied. Based on the variety of applications ofmethane reforming a selection of supports was made including fluorites, perovskites andaluminum oxide. In the absence of rhodium, the perovskite and fluorite supports, I.e.SrFe0.67Co0.33O3+δ, La0.6Sr0.4Co0.2Fe0.8O3+δ, Ce0.8Gd0.2O1.9+δ, and CeO2-ZrO2 all showedactivity for the total combustion of methane but proved to be poor reforming catalysts.Impregnation of the fluorite and alumina supports with rhodium provided active catalysts for the reforming of methane. The activity of perovskite-supported rhodium appeared to dependstrongly on the reducibility of the perovskite. Rhodium supported on La0.77Sr0.13MnO3+δ is areasonably active catalyst, but it deactivates rapidly. Rhodium supported on mixed valenceoxides SrFe0.67Co0.33O3+δ or La0.6Sr0.4Co0.2Fe0.8O3+δ is hardly more active than the bare support.Application of other metals active in reforming such as platinum, ruthenium, nickel, orpalladium on La0.6Sr0.4Co0.2Fe0.8O3+δ lead to surprisingly low catalytic activity. For supportedrhodium catalysts a relation is suggested between reducibility of the support materials andcatalytic activity for the reforming of methane, which is presently under further investigation.