Abstract: A supported core-shell bimetallic catalyst with high selectivity, and preparation method and an application thereof are provided. SBA-15 is used as support, platinum (Pt) is used as active component, 3d transition metal is used as cocatalysts. In the core-shell bimetallic catalyst formed by the 3d transition metal and Pt, in one aspect, by the addition of the 3d metal in the core, the d-band center of surface Pt atoms is down shifted, and the absorption of propylene is weakened, thereby improving the selectivity for propylene. In another aspect, the use of Pt is reduced by the addition of the 3d transition metal, improving the utilization of Pt. The catalyst is applicable in a hydrogen atmosphere, has a good effect on the preparation of propylene by propane dehydrogenation and causes high dehydrogenation activity under high temperature conditions. The total selectivity for propylene may reach 85%, which achieves high propylene selectivity.

Abstract: A molybdenum-vanadium bimetal oxide catalyst having a molecular formula of Mo1Vy, where y represents an atomic molar ratio of vanadium and molybdenum. An oxygen support Mo1Vy is prepared by an impregnation method including impregnation, drying, calcination, and tablet pressing. In the dehydrogenation reaction of a light alkane to an alkene over the supported molybdenum-vanadium bimetal oxide, the reaction temperature is 450° C.-550° C. Propane can be oxidized and dehydrogenated to produce propylene with a high activity and high selectivity. A conversion rate of propane remains at 30%-40%, and a selectivity for propylene is 80%-90%. A fresh oxygen support changes from a high-valence state to a low-valence state after reacting with propane. A low-valence state oxygen support reacts with air or oxygen to be oxidized to a high-valence state, and recovers lattice oxygen and cycles again.

Abstract: A supported core-shell bimetallic catalyst with high selectivity for propane dehydrogenation, containing platinum (Pt) as active species, 3d transition metals (Fe, Co and Ni) as promoters and SBA-15 as support. The addition of 3d metals and the formation of Pt3d alloys in subsurface result in a core-shell bimetallic catalyst which promotes the propene selectivity by decreasing the d-band center of surface Pt atoms and facilitating the desorption of propene on Pt. In another aspect, the reduced usage of Pt is achieved with the addition of 3d transition metals as well as the increased utilization of Pt atoms. The catalyst can be effectively used as a catalyst for the preparation of propene by propane dehydrogenation and 85% of propene selectivity can be achieved in propane dehydrogenation.

Abstract: A molybdenum-vanadium bimetallic oxide catalyst and its application in the chemical looping oxidative dehydrogenation of alkane. The molecular formula of molybdenum-vanadium bimetallic oxide catalyst is MoVy and y represents the atomic molar ratio of vanadium and molybdenum. The supported MoVy catalyst is prepared by impregnation method, following the drying, calcination and tablet pressing. The reaction temperature was 450-550° C., and propane could be oxidized and dehydrogenated to propylene with high activity and selectivity, with propane conversion rate remaining at 30-40% and propylene selectivity at 80-90%. The fresh catalysts were reduced to the lower valence states with the lattice oxygen diffusion to propane. After the dehydrogenation, the reduced samples were regenerated to recover to the initial state and regain the lattice oxygen. During the redox cycles, the reaction performance remains stable, which can be used in the fixed bed reactor, moving bed reactor or circulating fluidized bed.