The present specification relates to a preparation method for rod-shaped molybdenum oxide and a preparation method for a molybdenum oxide composite, the preparation method for rod-shaped molybdenum oxide according to the present invention may be carried out under low temperature and pressure conditions, and thus has an advantage in that it is possible to mass produce rod-shaped molybdenum oxide, and the preparation method for a molybdenum oxide composite according to the present invention has an advantage in that the molybdenum oxide composite may be synthesized at a temperature which is equal to or less than the boiling point of ethanol, and the amount of an ethanol solvent used is reduced.

The present invention relates to energy saving method and apparatus for preparing styrene and alpha-methylstyrene concurrently, by which economic feasibility may be improved by reusing energy during preparing styrene and alpha-methylstyrene concurrently.

A photocatalytic member comprises a base and a photocatalytic layer fixed on the base. The photocatalytic layer comprises first photocatalyst particles being visible light responsive photocatalyst particles for hydrogen generation, second photocatalyst particles being visible light responsive photocatalyst particles for oxygen generation, and conductive particles which are provided between the first photocatalyst particle and the second photocatalyst particle, have Fermi level at a negative position relative to an electronic energy level at the upper end of the valence band of the first photocatalyst particle and at a positive position relative to an electronic energy level at the bottom end of the conduction band of the second photocatalyst particle, and are able to store an electron and a hole. In the photocatalytic layer, the conductive particles are located to be coupled to both the first photocatalyst particles and the second photocatalyst particles.

An oxidative dehydrogenation catalyst having: a structure having a formula Mo.sub.vV.sub.wNb.sub.yBi.sub.zO.sub.x, where v is 1, w is from 0.1 to 0.5, y is from 0.001 to 0.3, z is from 0.01 to 0.3, and x is the oxygen content required to charge-balance the structure. The oxidative dehydrogenation catalyst has a Pba2-32 space group, characterized by reflections determined with CuK.sub. X-ray diffraction (XRD) as follows.

An oxidative dehydrogenation catalyst having: a structure having a formula Mo.sub.vV.sub.wNb.sub.yBi.sub.zO.sub.x, where v is 1, w is from 0.1 to 0.5, y is from 0.001 to 0.3, z is from 0.01 to 0.3, and x is the oxygen content required to charge-balance the structure. The oxidative dehydrogenation catalyst has a Pba2-32 space group, characterized by reflections determined with CuK.sub. X-ray diffraction (XRD) as follows.

Process for producing a multimetal oxide catalyst comprising molybdenum, chromium and at least one further metal by mixing of a pulverulent multimetal oxide comprising molybdenum and at least one further metal but no chromium with pulverulent chromium(III) oxide and thermal treatment of the resulting pulverulent mixture in the presence of oxygen at a temperature in the range from 350 C. to 650 C.

Process for producing a multimetal oxide catalyst comprising molybdenum, chromium and at least one further metal by mixing of a pulverulent multimetal oxide comprising molybdenum and at least one further metal but no chromium with pulverulent chromium(III) oxide and thermal treatment of the resulting pulverulent mixture in the presence of oxygen at a temperature in the range from 350 C. to 650 C.

The present invention relates to a bismuth molybdate-based composite oxide catalyst having a microporous zeolite coating layer on the surface thereof and thus having high selectivity for 1,3-butadiene, a method of preparing the same, and a method of preparing 1,3-butadiene using the same. The catalyst has a microporous zeolite coating layer, and thus enables only gaseous products (light) to selectively pass through the zeolite coating layer, improving selectivity for 1,3-butadiene.

The present invention relates to a bismuth molybdate-based composite oxide catalyst having a microporous zeolite coating layer on the surface thereof and thus having high selectivity for 1,3-butadiene, a method of preparing the same, and a method of preparing 1,3-butadiene using the same. The catalyst has a microporous zeolite coating layer, and thus enables only gaseous products (light) to selectively pass through the zeolite coating layer, improving selectivity for 1,3-butadiene.

A method for producing diene comprises a step 1 of obtaining a straight chain internal olefin by removing a branched olefin from a raw material including at least the branched olefin and a straight chain olefin; and a step 2 of producing diene from the internal olefin by oxidative dehydrogenation using a first catalyst and a second catalyst, and the first catalyst has a complex oxide including bismuth, molybdenum and oxygen, and the second catalyst includes at least one selected from the group consisting of silica and alumina.