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.

The present invention relates to a process for producing mixed oxide catalysts on the basis of molybdenum and bismuth oxides in which the precursor compounds of the components of mixed oxide catalysts provided in the form of a solution and/or suspension are subjected to a spray-drying with a specific temperature regime and the spray particles obtained in this way are then calcined to yield a catalytic active mass, and to the mixed oxide catalysts obtainable by this process and to the use of these catalysts in the partial oxidation of olefms, in particular in the partial gas phase oxidation of propene to acrolein and acrylic acid. The spray drying of the precursor compounds containing solution or suspension is performed in concurrent with a gas stream having a specific entrance temperature. Alternatively, when the main gas stream has a higher entrance temperature, an additional colder gas stream can be fed in downstream. The thus obtained mixed oxide catalysts give lower a maximum temperature in the hot spot of catalyst fixed bed when they are used in the partial gas phase oxidation of olefms.

The present invention relates to a process for producing mixed oxide catalysts on the basis of molybdenum and bismuth oxides in which the precursor compounds of the components of mixed oxide catalysts provided in the form of a solution and/or suspension are subjected to a spray-drying with a specific temperature regime and the spray particles obtained in this way are then calcined to yield a catalytic active mass, and to the mixed oxide catalysts obtainable by this process and to the use of these catalysts in the partial oxidation of olefms, in particular in the partial gas phase oxidation of propene to acrolein and acrylic acid. The spray drying of the precursor compounds containing solution or suspension is performed in concurrent with a gas stream having a specific entrance temperature. Alternatively, when the main gas stream has a higher entrance temperature, an additional colder gas stream can be fed in downstream. The thus obtained mixed oxide catalysts give lower a maximum temperature in the hot spot of catalyst fixed bed when they are used in the partial gas phase oxidation of olefms.

A supported molded catalyst having increased hardness, the supported molded catalyst being capable of improving the long-term stability of a reaction for producing a conjugated diolefin by catalytic oxidative dehydrogenation from a mixed gas including a monoolefin having 4 or more carbon atoms and molecular oxygen; and a method for producing the catalyst is provided. A molded catalyst for conjugated diolefin production, the molded catalyst being a catalyst for producing a conjugated diolefin by a catalytic oxidative dehydrogenation reaction from a mixed gas including a monoolefin having 4 or more carbon atoms and molecular oxygen, and being produced by molding a composite metal oxide and a glass fiber-like inorganic auxiliary agent.

A supported molded catalyst having increased hardness, the supported molded catalyst being capable of improving the long-term stability of a reaction for producing a conjugated diolefin by catalytic oxidative dehydrogenation from a mixed gas including a monoolefin having 4 or more carbon atoms and molecular oxygen; and a method for producing the catalyst is provided. A molded catalyst for conjugated diolefin production, the molded catalyst being a catalyst for producing a conjugated diolefin by a catalytic oxidative dehydrogenation reaction from a mixed gas including a monoolefin having 4 or more carbon atoms and molecular oxygen, and being produced by molding a composite metal oxide and a glass fiber-like inorganic auxiliary agent.

Disclosed is a catalyst system, and its methods of preparation for producing, among others, alkenes and/or saturated or unsaturated oxygenates and, which include at least one of an aldehyde and an acid (such as propyl aldehyde, acrolein, acrylic acid, isobutyl aldehyde, methacrolein, methacrylic acid), comprising subjecting the corresponding C3 to C4 aliphatic alcohols that are derivable from biomass, such as, propanols, propanediols, and isobutanol, to a vapor phase process over the catalytic system described herein in the presence of a gas mixture of oxygen, air or nitrogen and/or other suitable diluting gas. In the case where a C3 aliphatic alcohol is subjected to a vapor phase catalytic process over the said catalytic system in the presence of air or oxygen, and a co-fed gas, such as nitrogen or other diluting gas, the product is at least one of propylene, propyl aldehyde, acrolein and acrylic acid. In the case where isobutanol is subjected to such a process, the product is at least one of isobutylene, isobutyl aldehyde, methacrolein and methacrylic acid. The catalyst system comprises a single catalytic zone or multi-catalytic zones, in each of which the composition of the co-feed and other reaction parameter can be independently controlled.

Disclosed is a catalyst system, and its methods of preparation for producing, among others, alkenes and/or saturated or unsaturated oxygenates and, which include at least one of an aldehyde and an acid (such as propyl aldehyde, acrolein, acrylic acid, isobutyl aldehyde, methacrolein, methacrylic acid), comprising subjecting the corresponding C3 to C4 aliphatic alcohols that are derivable from biomass, such as, propanols, propanediols, and isobutanol, to a vapor phase process over the catalytic system described herein in the presence of a gas mixture of oxygen, air or nitrogen and/or other suitable diluting gas. In the case where a C3 aliphatic alcohol is subjected to a vapor phase catalytic process over the said catalytic system in the presence of air or oxygen, and a co-fed gas, such as nitrogen or other diluting gas, the product is at least one of propylene, propyl aldehyde, acrolein and acrylic acid. In the case where isobutanol is subjected to such a process, the product is at least one of isobutylene, isobutyl aldehyde, methacrolein and methacrylic acid. The catalyst system comprises a single catalytic zone or multi-catalytic zones, in each of which the composition of the co-feed and other reaction parameter can be independently controlled.

A method for converting alkanes to olefins includes contacting a feed stream comprising alkanes with an oxidative dehydrogenation that does not comprise tellurium catalyst in a reaction zone and dehydrogenating the alkanes without a co-feed of oxygen to yield a product stream having olefins. The oxidative dehydrogenation catalyst has the formula: Mo.sub.vV.sub.wNb.sub.yA.sub.zO.sub.x, where v is 1.0, w is from 0.1 to 0.5, y is from 0.001 to 0.3, A is Bi, Sb, Pr, or mixtures thereof, z is from 0.01 to 0.3, and x charge-balances the structure. The oxidative dehydrogenation catalyst has a crystallographic structure with Pba2-32 space group, characterized by reflections determined with Cu-K.sub. X-ray diffraction (XRD) as follows.

A method for converting alkanes to olefins includes contacting a feed stream comprising alkanes with an oxidative dehydrogenation that does not comprise tellurium catalyst in a reaction zone and dehydrogenating the alkanes without a co-feed of oxygen to yield a product stream having olefins. The oxidative dehydrogenation catalyst has the formula: Mo.sub.vV.sub.wNb.sub.yA.sub.zO.sub.x, where v is 1.0, w is from 0.1 to 0.5, y is from 0.001 to 0.3, A is Bi, Sb, Pr, or mixtures thereof, z is from 0.01 to 0.3, and x charge-balances the structure. The oxidative dehydrogenation catalyst has a crystallographic structure with Pba2-32 space group, characterized by reflections determined with Cu-K.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.