A catalyst includes a support, where the support includes an external surface, about 60 wt % to about 99 wt % silica, and about 1.0 wt % to about 5.0 wt % alumina. A catalytic layer is disposed within the support adjacent to the external surface, where the catalytic layer further includes Pd, Au, and potassium acetate (KOAc). In the catalyst, (a) the KOAc is from about 60 kg/m.sup.3 to about 150 kg/m.sup.3 of the catalyst; or (b) the catalytic layer has an average thickness from about 50 m to about 150 m; or (c) both (a) and (b). The catalyst also possesses a Brunauer-Emmett-Teller surface area of about 130 m.sup.2/g to about 300 m.sup.2/g and a geometric surface area per packed bed volume from about 550 m.sup.2/m.sup.3 to about 1500 m.sup.2/m.sup.3. The catalyst is highly active for the synthesis of vinyl acetate monomer and exhibits a high selectivity for vinyl acetate monomer.

The invention relates to a process for the production of an alkene by alkane oxidative dehydrogenation, comprising: (a) subjecting a stream comprising an alkane to oxidative dehydrogenation conditions, comprising contacting the alkane with oxygen in the presence of a catalyst comprising a mixed metal oxide, resulting in a stream comprising alkene, unconverted alkane, water, carbon dioxide, unconverted oxygen, carbon monoxide and optionally an alkyne; (b) removing water from at least part of the stream comprising alkene, unconverted alkane, water, carbon dioxide, unconverted oxygen, carbon monoxide and optionally an alkyne resulting from step (a), resulting in a stream comprising alkene, unconverted alkane, carbon dioxide, unconverted oxygen, carbon monoxide and optionally alkyne; (c) removing unconverted oxygen, carbon monoxide and optionally alkyne from at least part of the stream comprising alkene, unconverted alkane, carbon dioxide, unconverted oxygen, carbon monoxide and optionally alkyne resulting from step (b), wherein carbon monoxide and optionally alkyne are oxidized into carbon dioxide, resulting in a stream comprising alkene, unconverted alkane and carbon dioxide; (d) optionally removing carbon dioxide from at least part of the stream comprising alkene, unconverted alkane in and carbon dioxide resulting from step (c), resulting in a stream comprising alkene and unconverted alkane; (e) optionally separating at least part of the stream comprising alkene and unconverted alkane resulting from step (d), into a stream comprising alkene and a stream comprising unconverted alkane; (f) optionally recycling unconverted alkane from at least part of the stream comprising unconverted alkane resulting from step (e), to step (a).

The present disclosure relates to fluid bed processes that utilize silica particles as a fluidization aid. The process comprises reacting one or more reactants in a reactor comprising a fluid bed to form a product. The fluid bed comprises a catalyst composition comprising a catalyst and an inert additive composition comprising silica particles from 0.5 wt % to 30 wt %, based on the total weight of the catalyst composition. The silica particles are discrete, inert particles that are mixed with the catalyst in the fluid bed.

The invention relates to a method for producing a pellet, in particular for a catalytic convertor and/or static mixer. The method comprises a trimming and/or deforming of at least one layer of metal foam material into a pellet shape.

The invention relates to an oxygen carrier solid, its preparation and its use in a method of combustion of a hydrocarbon feedstock by active mass chemical-looping oxidation-reduction, i.e. chemical-looping combustion (CLC). The solid, which is in the form of particles, comprises an oxidation-reduction active mass composed of metal oxide(s) dispersed in a ceramic matrix comprising at least one oxide with a melting point higher than 1500 C., such as alumina, and has, initially, a specific macroporous texture. The oxygen carrier solid is prepared from an aqueous suspension containing precursor oxide grains for the ceramic matrix that have a specific size, by a spray-drying technique.

The invention relates to an oxygen carrier solid, its preparation and its use in a method of combustion of a hydrocarbon feedstock by active mass chemical-looping oxidation-reduction, i.e. chemical-looping combustion (CLC). The solid, which is hi the form of particles, comprises an oxidation-reduction active mass composed of metal oxide(s) dispersed in a ceramic matrix comprising at least at least one feldspar or feldspathoid with a melting point higher than 1500 C., such as celsian, and has, initially, a specific macroporous texture. The oxygen carrier solid is prepared from a precursor of the ceramic matrix, obtained from a macroporous zeolitic material with zeolite crystals of a specific size, and a precursor of the oxidation-reduction active mass.

Disclosed are an extruded honeycomb catalyst, a process for preparing the catalyst, a method for reducing NOx in the exhaust gas from an internal combustion engine by using the catalyst, and a method for treatment of the emission gas generated from power plant comprising exposing the emission gas to the catalyst.

The present invention relates to a method of improving the corrosion resistance of a metal substrate surface using an oxygen reduction catalyst, which may improve the corrosion resistance of the metal substrate surface by coating the metal substrate surface with the oxygen reduction catalyst so that the metal substrate surface is changed to a passive state through the action of the oxygen reduction catalyst in an environment in which a stable oxide layer is not spontaneously formed on the metal substrate surface. The present invention has an advantage in that it can dramatically improve the corrosion resistance of the metal substrate under a corrosive environment by allowing a recoverable oxide layer to be formed on the metal substrate surface through the action of the oxygen reduction catalyst, applied to the surface, even in an environment in which an oxide layer is not spontaneously formed on the metal substrate.

Particles for an exhaust gas purification catalyst including: inorganic oxide particles; and an inorganic coating layer covering the inorganic oxide particles. The particles for an exhaust gas purification catalyst have reduced cumulative pore volume in a pore diameter range of 0.1-20 m compared to a cumulative pore volume in a pore diameter range of 0.1-20 m of inorganic oxide particles before being coated with the inorganic coating layer. Accordingly, the particles for an exhaust gas purification catalyst have a higher thermal conductivity than the inorganic oxide particles before being coated with the inorganic coating layer.

A method of forming a batch of porous catalytic carrier filaments may include providing a precursor mixture, forcing the precursor mixture at a fixed rate through an orifice and then through a multiplicity of perforations in a belt, where the belt moves across and in tight registry with said orifice to form a batch of precursor catalytic carrier filaments, drying the batch of precursor porous catalytic carrier filaments to form the batch of porous catalytic carrier filaments, and firing (i.e. calcining) the batch of greenware porous catalytic carrier filaments to form the batch of porous catalytic carrier filaments. The batch of porous catalytic carrier filaments may have an average pore volume of at least about 0.1 cm.sup.3/g.