A process includes reacting a feed stream containing ethanol and optionally acetaldehyde in a dehydration reactor in the presence of a dehydration catalyst system having a Group 4 or Group 5 metal oxide and a support. The process includes obtaining a product stream containing butadiene from the dehydration reactor. Another process includes reacting a feed stream containing ethanol and optionally acetaldehyde in a dehydration reactor in the presence of a dehydration catalyst system containing a tungsten oxide supported on a zeolite or a tantalum oxide supported on a zeolite. The process includes obtaining a product stream containing butadiene from the dehydration reactor.

Increase propane dehydrogenation activity of a partially deactivated dehydrogenation catalyst by heating the partially deactivated catalyst to a temperature of at least 660° C., conditioning the heated catalyst in an oxygen-containing atmosphere and, optionally, stripping molecular oxygen from the conditioned catalyst.

Increase propane dehydrogenation activity of a partially deactivated dehydrogenation catalyst by heating the partially deactivated catalyst to a temperature of at least 660° C., conditioning the heated catalyst in an oxygen-containing atmosphere and, optionally, stripping molecular oxygen from the conditioned catalyst.

A method of selectively catalysing the reduction of oxides of nitrogen (NO.sub.x) including nitrogen monoxide in an exhaust gas of a stationary source of NO.sub.x emissions also containing oxides of sulfur (SO.sub.x) comprising the steps of passively oxidising nitrogen monoxide to nitrogen dioxide (NO.sub.2) over an oxidation catalyst comprising a platinum group metal so that a NO.sub.2/NO.sub.x content is from 40-60%; introducing a nitrogenous reductant into the exhaust gas; and contacting exhaust gas having the 40-60% NO.sub.2/NO.sub.x content and containing the nitrogenous reductant with a selective catalytic reduction (SCR) catalyst comprising an aluminosilicate zeolite promoted with copper.

A method of selectively catalysing the reduction of oxides of nitrogen (NO.sub.x) including nitrogen monoxide in an exhaust gas of a stationary source of NO.sub.x emissions also containing oxides of sulfur (SO.sub.x) comprising the steps of passively oxidising nitrogen monoxide to nitrogen dioxide (NO.sub.2) over an oxidation catalyst comprising a platinum group metal so that a NO.sub.2/NO.sub.x content is from 40-60%; introducing a nitrogenous reductant into the exhaust gas; and contacting exhaust gas having the 40-60% NO.sub.2/NO.sub.x content and containing the nitrogenous reductant with a selective catalytic reduction (SCR) catalyst comprising an aluminosilicate zeolite promoted with copper.

The present invention relates to a process for the preparation of catalyst(s), comprising the cokneading of boehmite with an active phase comprising a salt of heteropolyanion of Keggin and/or lacunary Keggin and/or substituted lacunary Keggin and/or Anderson and/or Strandberg type, and their mixtures, exhibiting, in its structure, molybdenum and cobalt and/or nickel. The present invention also relates to a process for the hydrotreating and/or hydroconversion of a heavy hydrocarbon feedstock in the presence of catalyst(s) prepared according to said process.

The present invention relates to a process for the preparation of catalyst(s), comprising the cokneading of boehmite with an active phase comprising a salt of heteropolyanion of Keggin and/or lacunary Keggin and/or substituted lacunary Keggin and/or Anderson and/or Strandberg type, and their mixtures, exhibiting, in its structure, molybdenum and cobalt and/or nickel. The present invention also relates to a process for the hydrotreating and/or hydroconversion of a heavy hydrocarbon feedstock in the presence of catalyst(s) prepared according to said process.

Methods for making a supported chromium catalyst are disclosed, and can comprise contacting a silica-coated alumina containing at least 30 wt. % silica with a chromium-containing compound in a liquid, drying, and calcining in an oxidizing atmosphere at a peak temperature of at least 650° C. to form the supported chromium catalyst. The supported chromium catalyst can contain from 0.01 to 20 wt. % chromium, and typically can have a pore volume from 0.5 to 2 mL/g and a BET surface area from 275 to 550 m.sup.2/g. The supported chromium catalyst subsequently can be used to polymerize olefins to produce, for example, ethylene-based homopolymers and copolymers having high molecular weights and broad molecular weight distributions.

Methods for making a supported chromium catalyst are disclosed, and can comprise contacting a silica-coated alumina containing at least 30 wt. % silica with a chromium-containing compound in a liquid, drying, and calcining in an oxidizing atmosphere at a peak temperature of at least 650° C. to form the supported chromium catalyst. The supported chromium catalyst can contain from 0.01 to 20 wt. % chromium, and typically can have a pore volume from 0.5 to 2 mL/g and a BET surface area from 275 to 550 m.sup.2/g. The supported chromium catalyst subsequently can be used to polymerize olefins to produce, for example, ethylene-based homopolymers and copolymers having high molecular weights and broad molecular weight distributions.

The disclosed subject matter presents a catalyst or catalyst composition as well as the methods of making and using the catalyst or catalyst composition. In one aspect, the disclosed subject matter relates to a catalyst comprising CoMn.sub.aSi.sub.bX.sub.cY.sub.dO.sub.x wherein in X comprises an element from Group 11; Y comprises an element from Group 12; a ranges from 0.8 to 1.2; b ranges from 0.1 to 1; c ranges from 0.01 to 0.05; d ranges from 0.01 to 0.05; x is a number determined by the valency requirements of the other elements present; and wherein the catalyst converts synthesis gas to at least one olefin.