Disclosed are a molybdenum based composite oxide catalyst, its preparation method and use. The catalyst has the following general formula: BiMo.sub.xM.sub.yN.sub.zO.sub.a; wherein M is one of V, Cr, Mn, Fe, Co, Ni and Cu, or a mixture of two or more of V, Cr, Mn, Fe, Co, Ni and Cu in any ratio; N is one of Na, K, Cs, Ca and Ba, or a mixture of two or more of Na, K, Cs, Ca and Ba in any ratio; x=0.5˜20; y=0.05˜20; z=0.01˜5; a is a number satisfying the valance of each atom. The catalyst is prepared by the following method: firstly mixing a certain amount of the lead metal oxides according to the chemical proportion and then grinding the mixture with high-energy ball milling for a period of time to obtain the molybdenum based composite oxide catalyst. The catalyst exhibits excellent performance when using for preparation of butadiene by oxidative dehydrogenation of butene, and the preparation process is simple, controllable, and repeatable. Waste water or waste gas that is difficult to be treated is not produced during preparation.

This disclosure relates to photocatalytic polyoxometalate compositions of tungstovanadates and uses as water oxidation catalysts. In certain embodiments, the disclosure relates to compositions comprising water, a complex of a tetra-metal oxide cluster and VW.sub.9O.sub.34 ligands, and a photosensitizer. Typically, the metal oxide cluster is Co. In certain embodiments, the disclosure relates to electrodes and other devices comprising water oxidation catalysts disclosed herein and uses in generating fuels and electrical power from solar energy.

This disclosure relates to photocatalytic polyoxometalate compositions of tungstovanadates and uses as water oxidation catalysts. In certain embodiments, the disclosure relates to compositions comprising water, a complex of a tetra-metal oxide cluster and VW.sub.9O.sub.34 ligands, and a photosensitizer. Typically, the metal oxide cluster is Co. In certain embodiments, the disclosure relates to electrodes and other devices comprising water oxidation catalysts disclosed herein and uses in generating fuels and electrical power from solar energy.

Disclosed is a multi-component bismuth molybdate catalyst for production of butadiene which comprises bismuth, molybdenum and at least one metal having a monovalent, divalent or trivalent cation, and further comprises cesium and potassium and thus has advantages of improving conversion ratio, yield and selectivity of butadiene and of providing stability of process operation.

Disclosed is a multi-component bismuth molybdate catalyst for production of butadiene which comprises bismuth, molybdenum and at least one metal having a monovalent, divalent or trivalent cation, and further comprises cesium and potassium and thus has advantages of improving conversion ratio, yield and selectivity of butadiene and of providing stability of process operation.

The disclosure provides an improved endothermic hydrocarbon conversion process that comprises reacting a hydrocarbon with a multi-component catalyst bed, and regenerating the catalyst bed with air, where the air used in regeneration step and hydrocarbon are at low air to hydrocarbon ratios and optionally at near-atmospheric pressures.

The disclosure provides an improved endothermic hydrocarbon conversion process that comprises reacting a hydrocarbon with a multi-component catalyst bed, and regenerating the catalyst bed with air, where the air used in regeneration step and hydrocarbon are at low air to hydrocarbon ratios and optionally at near-atmospheric pressures.

A method for producing a multiphase mixed-oxide catalyst including at least one active phase based on bismuth molybdate and one co-catalyst based on iron molybdate and at least one amongst the two elements cobalt and nickel, includes the following steps:

preparing a mixture of the precursors of said-mixed oxides in a solvent,

making said precursors react through a microwave-assisted hydrothermal reaction, and

isolating the mixed oxides to obtain the catalyst.

A catalyst and a catalytic system prepared in this manner are related to the method as well as the uses of this catalyst and of this catalytic system, in particular in the oxidation of propene into acrolein.

A method for producing a multiphase mixed-oxide catalyst including at least one active phase based on bismuth molybdate and one co-catalyst based on iron molybdate and at least one amongst the two elements cobalt and nickel, includes the following steps:

preparing a mixture of the precursors of said-mixed oxides in a solvent,

making said precursors react through a microwave-assisted hydrothermal reaction, and

isolating the mixed oxides to obtain the catalyst.

A catalyst and a catalytic system prepared in this manner are related to the method as well as the uses of this catalyst and of this catalytic system, in particular in the oxidation of propene into acrolein.

The present disclosure relates to metal oxide catalyst materials useful, for example, in the ammoxidation of propylene or isobutylene, processes for making them, and processes for making acrylonitrile and methacrylonitrile using such catalyst materials. In certain aspects, a catalyst material is a fused composite of a metal oxide catalyst and nanoparticulate silica, the nanoparticulate silica comprising in the range of about 40 wt % to about 80 wt % of silica having a particle size in the range of 10 nm to 35 nm, and in the range of about 20 wt % to about 60 wt % of silica having a particle size in the range of 36 nm to 80 nm. The metal oxide catalyst can be, for example, a molybdenum-containing mixed metal oxide catalyst.