The invention relates to a composition containing a catalyst suitable for producing ethylene and other C.sub.2+ hydrocarbons at high selectivity while improving both methane conversion and product yield. Particularly, the catalyst contains mixed metal oxides having at least one alkali earth metal and at least one rare earth metal along with an alkali metal promoter in the form of an alkali metal or in the form of an alkali metal tungstate. The invention further provides a method for preparing such a composition, using a calcination process to calcine the alkali metal promoters together with mixed metal oxides. Additionally, the invention further describes a process for producing C.sub.2+ hydrocarbons, using such a composition.

A bottoms cracking catalyst composition, comprising: about 30 to about 60 wt % alumina; greater than 0 to about 10 wt % of a dopant, measured as the oxide; about 2 to about 20 wt % reactive silica; about 3 to about 20 wt % of a component comprising peptizable boehmite, colloidal silica, aluminum chlorohydrol, or a combination of any two or more thereof; and about 10 to about 50 wt % of kaolin.

A bottoms cracking catalyst composition, comprising: about 30 to about 60 wt % alumina; greater than 0 to about 10 wt % of a dopant, measured as the oxide; about 2 to about 20 wt % reactive silica; about 3 to about 20 wt % of a component comprising peptizable boehmite, colloidal silica, aluminum chlorohydrol, or a combination of any two or more thereof; and about 10 to about 50 wt % of kaolin.

Synthesis of silanes with more than three silicon atoms are disclosed (i.e., Si.sub.nH.sub.(2n+2) with n=4-100). More particularly, the disclosed synthesis methods tune and optimize the isomer ratio by selection of process parameters such as temperature, residence time, and the relative amount of starting compounds, as well as selection of proper catalyst. The disclosed synthesis methods allow facile preparation of silanes containing more than three silicon atoms and particularly, the silanes containing preferably one major isomer. The pure isomers and isomer enriched mixtures are prepared by catalytic transformation of silane (SiH.sub.4), disilane (Si.sub.2H.sub.6), trisilane (Si.sub.3H.sub.8), and mixtures thereof.

The oxidative coupling of methane (OCM) and the oxidative dehydrogenation (ODH) of ethane and higher hydrocarbons is described using SO.sub.3 and sulfate, sulfite, bisulfite and metabifulfite salts as oxygen transfer agents in the presence of one or more elements selected from Groups 3 to 14 of the periodic table, optionally further in the presence of alkali or alkaline salts and/or sulfur-containing compounds.

A method for producing (meth)acrolein by vapor-phase catalytic oxidation of propylene or isobutylene in a multitubular reactor including a plurality of reaction tubes, the reaction tubes each including a reaction zone filled with a catalyst including molybdenum oxide and a cooling zone filled with an inert substance, wherein a temperature of a heat medium that flows outside the cooling zone is lower than a temperature of a heat medium that flows outside the reaction zone, and wherein the inert substance includes an inert substance having a major-axis length that is equal to or more than 1.7 times a major-axis length of the catalyst. A method for producing (meth)acrylic acid in which (meth)acrolein thus produced is converted to (meth)acrylic acid by vapor-phase catalytic oxidation.

A method for producing (meth)acrolein by vapor-phase catalytic oxidation of propylene or isobutylene in a multitubular reactor including a plurality of reaction tubes, the reaction tubes each including a reaction zone filled with a catalyst including molybdenum oxide and a cooling zone filled with an inert substance, wherein a temperature of a heat medium that flows outside the cooling zone is lower than a temperature of a heat medium that flows outside the reaction zone, and wherein the inert substance includes an inert substance having a major-axis length that is equal to or more than 1.7 times a major-axis length of the catalyst. A method for producing (meth)acrylic acid in which (meth)acrolein thus produced is converted to (meth)acrylic acid by vapor-phase catalytic oxidation.

A catalyst for oxidative coupling of methane, and preparation and application thereof. The catalyst comprises: a manganese sesquioxide, a tungstate, a manganese composite oxide having a perovskite structure and/or a spinel structure, and a carrier. The manganese sesquioxide, tungstate, and manganese composite oxide having a perovskite structure and/or a spinel structure are supported on the carrier, or the manganese sesquioxide and tungstate are supported on the admixture of the said manganese composite oxide having a perovskite structure and/or a spinel structure and the said carrier. Based on 100 parts by weight of the catalyst, the content of the manganese sesquioxide is a parts by weight, the content of the tungstate is b parts by weight, the content of the manganese composite oxide having the perovskite structure and/or the spinel structure is c parts by weight The content of the carrier is d parts by weight. 0<a≤20, 1≤b≤20, 1≤c≤40, 20≤d<98.

A catalyst for oxidative coupling of methane, and preparation and application thereof. The catalyst comprises: a manganese sesquioxide, a tungstate, a manganese composite oxide having a perovskite structure and/or a spinel structure, and a carrier. The manganese sesquioxide, tungstate, and manganese composite oxide having a perovskite structure and/or a spinel structure are supported on the carrier, or the manganese sesquioxide and tungstate are supported on the admixture of the said manganese composite oxide having a perovskite structure and/or a spinel structure and the said carrier. Based on 100 parts by weight of the catalyst, the content of the manganese sesquioxide is a parts by weight, the content of the tungstate is b parts by weight, the content of the manganese composite oxide having the perovskite structure and/or the spinel structure is c parts by weight The content of the carrier is d parts by weight. 0<a≤20, 1≤b≤20, 1≤c≤40, 20≤d<98.

Embodiments of the present disclosure are directed to hydrogen-selective oxygen carrier materials and methods of using hydrogen-selective oxygen carrier materials. The hydrogen-selective oxygen carrier material may comprise a core material, which includes a redox-active transition metal oxide; a shell material, which includes one or more alkali transition metal oxides; and a support material. The shell material may be in direct contact with at least a majority of an outer surface of the core material. At least a portion of the core material may be in direct contact with the support material. The hydrogen-selective oxygen carrier material may be selective to combust hydrogen in an environment that includes hydrogen and hydrocarbons.