The invention relates to a composition containing a catalyst having high catalytic stability for conducting oxidative coupling of methane (OCM) at high carbon efficiency, while improving both methane and oxygen conversion. Particularly, the inventive catalyst is a metal oxide supported catalyst, which contains an alkali metal promoter and a mixed metal oxide component having at least one alkali earth metal and at least one rare earth metal. The metal oxide support is selected in a manner, such that at least a portion of the metal oxide support is capable of reacting with at least a part or whole of the alkali metal promoter under conditions of calcination during catalyst preparation. The invention further provides a method for preparing such a metal oxide supported catalyst composition, using a calcination process. Additionally, the invention further describes a process for producing C.sub.2+ hydrocarbons, using such a catalyst composition.

The invention relates to a composition containing a catalyst having high catalytic stability for conducting oxidative coupling of methane (OCM) at high carbon efficiency, while improving both methane and oxygen conversion. Particularly, the inventive catalyst is a metal oxide supported catalyst, which contains an alkali metal promoter and a mixed metal oxide component having at least one alkali earth metal and at least one rare earth metal. The metal oxide support is selected in a manner, such that at least a portion of the metal oxide support is capable of reacting with at least a part or whole of the alkali metal promoter under conditions of calcination during catalyst preparation. The invention further provides a method for preparing such a metal oxide supported catalyst composition, using a calcination process. Additionally, the invention further describes a process for producing C.sub.2+ hydrocarbons, using such a catalyst composition.

Monodisperse polystyrene microspheres are self-assembled on a conductive surface of FTO glass by vertical deposition method to prepare three-dimensional ordered photonic crystal opal template; the three-dimensional ordered photonic crystal opal template is immersed in a solution containing rhodium source, titanium source and strontium source, and is then calcined to prepare a rhodium doped strontium titanate inverse opal material; and the rhodium doped strontium titanate inverse opal material is added to water containing pollutants, and is then subjected to illumination and/or ultrasonic treatment to complete the removal of the pollutants in the water. The three-dimensional ordered macroporous rhodium doped strontium titanate inverse opal material may be applied in the field of photocatalysis. Under the action of external force, a built-in electric field formed by the spontaneous polarization of the material may effectively separate the photo-induced carriers, which may thus enhance the photocatalytic performance and improve the photocatalytic efficiency.

Monodisperse polystyrene microspheres are self-assembled on a conductive surface of FTO glass by vertical deposition method to prepare three-dimensional ordered photonic crystal opal template; the three-dimensional ordered photonic crystal opal template is immersed in a solution containing rhodium source, titanium source and strontium source, and is then calcined to prepare a rhodium doped strontium titanate inverse opal material; and the rhodium doped strontium titanate inverse opal material is added to water containing pollutants, and is then subjected to illumination and/or ultrasonic treatment to complete the removal of the pollutants in the water. The three-dimensional ordered macroporous rhodium doped strontium titanate inverse opal material may be applied in the field of photocatalysis. Under the action of external force, a built-in electric field formed by the spontaneous polarization of the material may effectively separate the photo-induced carriers, which may thus enhance the photocatalytic performance and improve the photocatalytic efficiency.

A multilayer supported oxidative coupling of methane (OCM) catalyst composition (support, first single oxide layer, one or more mixed oxide layers, optional second single oxide layer) characterized by formula A.sub.aZ.sub.bE.sub.cD.sub.dO.sub.x/support; A is alkaline earth metal; Z is first rare earth element; E is second rare earth element; D is redox agent/third rare earth element; the first, second, third rare earth element are not the same; a=1.0; b=0.1-10.0; c=0.1-10.0; d=0-10.0; x balances oxidation states; first single oxide layer (Z.sub.b1O.sub.x1, b1=0.1-10.0; x1 balances oxidation states) contacts support and one or more mixed oxide layers; one or more mixed oxide layers (A.sub.a2Z.sub.b2E.sub.c2D.sub.d2O.sub.x2, a2=1.0; b2=0.1-10.0; c2=0.1-10.0; d2=0-10.0; x2 balances oxidation states; A.sub.aZ.sub.bE.sub.cD.sub.dO.sub.x and A.sub.a2Z.sub.b2E.sub.c2D.sub.d2O.sub.x2 are different) contacts first single oxide layer and optionally second single oxide layer, and second single oxide layer (AO), when present, contacts one or more mixed oxide layers and optionally first single oxide layer.

A multilayer supported oxidative coupling of methane (OCM) catalyst composition (support, first single oxide layer, one or more mixed oxide layers, optional second single oxide layer) characterized by formula A.sub.aZ.sub.bE.sub.cD.sub.dO.sub.x/support; A is alkaline earth metal; Z is first rare earth element; E is second rare earth element; D is redox agent/third rare earth element; the first, second, third rare earth element are not the same; a=1.0; b=0.1-10.0; c=0.1-10.0; d=0-10.0; x balances oxidation states; first single oxide layer (Z.sub.b1O.sub.x1, b1=0.1-10.0; x1 balances oxidation states) contacts support and one or more mixed oxide layers; one or more mixed oxide layers (A.sub.a2Z.sub.b2E.sub.c2D.sub.d2O.sub.x2, a2=1.0; b2=0.1-10.0; c2=0.1-10.0; d2=0-10.0; x2 balances oxidation states; A.sub.aZ.sub.bE.sub.cD.sub.dO.sub.x and A.sub.a2Z.sub.b2E.sub.c2D.sub.d2O.sub.x2 are different) contacts first single oxide layer and optionally second single oxide layer, and second single oxide layer (AO), when present, contacts one or more mixed oxide layers and optionally first single oxide layer.

Here disclosed is a composite catalyst for methane cracking and a method of producing the composite catalyst. The composite catalyst includes a substrate formed of metal oxide, and one or more catalytic transition metals solubilized in the metal oxide, wherein the metal oxide includes a metal which differs from the one or more catalytic transition metals, wherein the metal oxide forms a matrix which the one or more catalytic transition metals are solubilized in to render transition metal ions from the one or more catalytic transition metals, wherein the transition metal ions under a reducing atmosphere diffuse to reside as transition metal nanoparticles at a surface of the substrate and the transition metal nanoparticles under an oxidizing atmosphere diffuse away from the surface to reside as transition metal ions in the metal oxide, and wherein the transition metal nanoparticles at the surface induce carbon from the methane cracking to deposit on the transition metal nanoparticles and have the carbon deposited grow away from the substrate.

Here disclosed is a composite catalyst for methane cracking and a method of producing the composite catalyst. The composite catalyst includes a substrate formed of metal oxide, and one or more catalytic transition metals solubilized in the metal oxide, wherein the metal oxide includes a metal which differs from the one or more catalytic transition metals, wherein the metal oxide forms a matrix which the one or more catalytic transition metals are solubilized in to render transition metal ions from the one or more catalytic transition metals, wherein the transition metal ions under a reducing atmosphere diffuse to reside as transition metal nanoparticles at a surface of the substrate and the transition metal nanoparticles under an oxidizing atmosphere diffuse away from the surface to reside as transition metal ions in the metal oxide, and wherein the transition metal nanoparticles at the surface induce carbon from the methane cracking to deposit on the transition metal nanoparticles and have the carbon deposited grow away from the substrate.

A hydrocarbon reforming catalyst used for forming a synthetic gas containing hydrogen and carbon monoxide from a hydrocarbon-based gas, the hydrocarbon reforming catalyst containing a complex oxide having a perovskite structure, wherein the complex oxide has a crystal phase containing SrZrO.sub.3 as a primary component and contains Ru.

A hydrocarbon reforming catalyst used for forming a synthetic gas containing hydrogen and carbon monoxide from a hydrocarbon-based gas, the hydrocarbon reforming catalyst containing a complex oxide having a perovskite structure, wherein the complex oxide has a crystal phase containing SrZrO.sub.3 as a primary component and contains Ru.