Rare earth (Y, La, Ce)-promoted V-HMS mesoporous catalysts for oxidative dehydrogenation of propane

Abstract

The effect of rare earth (Y, La, Ce) oxides on hexagonal mesoporous silicas (HMS) silica supported vanadia catalysts for the oxidative dehydrogenation of propane was investigated. The doping of Y, La oxides into the V-HMS catalyst affords a significant promotion in the selectivity to propylene while the Ce oxide exhibits a reverse effect for the oxidative dehydrogenation process. The characterization results show that the doping of rare earth oxides results in a significant modification of the redox and acid properties of the V-HMS catalysts. In addition, the formation of a new active phase of rare earth orthovanadates over the modified V-HMS catalysts was also identified. The correlation between the structural changes and the selectivity of the catalysts implied that the formation of new active phase of LaVO 4 and YVO 4 might be responsible for the improved catalytic performance.