Abstract: A method for producing a multimetal oxide catalyst comprises preparation of a precursor composition, exposing said precursor composition to elevated temperatures to activate the composition, and grinding the activated composition. The preparation of the precursor composition comprises: a) forming a plasticized precursor composition from the constituents of the composition; b) discharging the plasticized precursor composition from an extruder having at least one die to form extrudates; c) allowing the extrudates to drop onto a transfer surface disposed beneath the at least one die whereby the extrudates break into pieces which come to rest on the transfer surface; d) transferring the pieces to at least one drying chamber; and e) moving the pieces, through the at least one drying chamber on an air permeable drying conveyor belt; wherein steps b) through d) are carried out under reduced pressure. The method allows the production of a multimetal oxide catalyst with uniform characteristics.

Abstract: The invention relates to an oxidation catalyst comprising at least one inorganic, oxidic or ceramic, shaped support body having a BET surface area of less than 0.5 m2/g, based on the support, which is at least partly coated with a catalytically active multielement oxide, the catalyst being precious metal-free and the shaped support body having the form of a saddle whose saddle surface is curved oppositely in the two principal directions, to a process for producing it, to its use in various catalytic gas phase oxidations, and to corresponding processes for catalytic gas phase oxidation.

Abstract: A hollow cylindrical shaped catalyst body for gas phase oxidation of an alkene to an ?,?-unsaturated aldehyde and/or an ?,?-unsaturated carboxylic acid comprises a compacted multimetal oxide having an external diameter ED, an internal diameter ID and a height H, wherein ED is in the range from 3.5 to 4.5 mm; the ratio q=ID/ED is in the range from 0.4 to 0.55; and the ratio p=H/ED is in the range from 0.5 to 1. The shaped catalyst body is mechanically stable and catalyzes the partial oxidation of an alkene to the products of value with high selectivity. It provides a sufficiently high catalyst mass density of the catalyst bed and good long-term stability with acceptable pressure drop.

Abstract: This invention relates to a method for the preparation of a hydrocarbon synthesis catalyst material, in the form of a hydrocarbon synthesis catalyst precursor and/or catalyst, preferably, a Fischer Tropsch synthesis catalyst precursor and/or catalyst. The invention also extends to the use of a catalyst precursor and/or catalyst prepared by the method according to the invention in a hydrocarbon synthesis process, preferably, a Fischer Tropsch synthesis process. According to this invention, a method for the preparation of a hydrocarbon synthesis catalyst material includes the steps of treating Fe(II) carboxylate in solution with an oxidizing agent to convert it to Fe(III) carboxylate in solution under conditions which ensure that such oxidation does not take place simultaneously with any dissolution of Fe(0); and hydrolyzing the Fe(III) carboxylate solution resulting from step (iii) and precipitating one or more Fe(III) hydrolysis products.

Abstract: Shaped catalyst bodies comprising a multielement oxide I having the general stoichiometry I [Bi1WbOx]a[Mo12Z1cZ2dFeeZ3fZ4gZ5hOy]1 (I), where Z1=Ni or Co, Z2=alkali metal or alkaline earth metal, Z3=zinc, phosphorus, arsenic, boron, antimony, tin, cerium, vanadium, chromium or bismuth, Z4=silicon, aluminum, titanium, tungsten or zirconiurn, Z5=copper, silver, gold, yttrium, lanthanum and lanthanides, a=0.1 to 3, b=0.1 to 10, c=1 to 10, d=0.01 to 2, e=0.01 to 5, f=0 to 5, g=0 to 10, h=0 to 1 and x, y=numbers determined by the valence and abundance of the elements other than oxygen in I, as active composition are produced by preforming a mixed oxide Bi1WbOx by coprecipitation from an aqueous environment at a pH in the range from 1.

Abstract: What is described is a catalyst for preparation of an ?,?-unsaturated carboxylic acid by gas phase oxidation of an ?,?-unsaturated aldehyde, comprising a shaped support body with an active composition applied thereto, wherein the active composition coverage q q = Q ( 100 - Q ) ? S m is at most 0.3 mg/mm2, where Q is the active composition content of the catalyst in % by weight and Sm is the specific geometric surface area of the shaped support body in mm2/mg. Also described are a process for preparing the catalyst and a process for preparing an ?,?-unsaturated carboxylic acid by gas phase oxidation of an ?,?-unsaturated aldehyde over a fixed catalyst bed comprising a bed of the catalyst. The catalyst, with constantly high conversion of acrolein, reduces overoxidation to COx and increases the selectivity of acrylic acid formation.

Abstract: A process for preparing (meth)acrylic acid by heterogeneously catalyzed gas phase partial oxidation of (meth)acrolein over a multimetal oxide composition which comprises the elements Mo, V and W and is obtained by a hydrothermal preparation route, and the multimetal oxide composition obtainable by this preparation route.

Abstract: An ?,?-unsaturated aldehyde and/or an ?,?-unsaturated carboxylic acid are prepared by gas phase oxidation of alkene with molecular oxygen over a fixed catalyst bed comprising a bed of hollow cylindrical shaped catalyst bodies having a multimetal oxide active composition. The fixed catalyst bed comprises at least three successive reaction zones; the highest local temperature in the fixed catalyst bed does not occur in the reaction zone closest to the reactor outlet; the highest local temperature in the fixed catalyst bed does not occur in the reaction zone closest to the reactor inlet; and the value WT=(ED?ID)/2 in the reaction zone in which the highest local temperature in the fixed catalyst bed occurs is lower than in the other reaction zones, in which ED is the external diameter and ID is the internal diameter of the shaped catalyst body. The yield of the products of value is enhanced in this way.

Abstract: The invention relates to an oxidation catalyst comprising at least one inorganic, oxidic or ceramic, shaped support body having a BET surface area of less than 0.5 m2/g, based on the support, which is at least partly coated with a catalytically active multielement oxide, the catalyst being precious metal-free and the shaped support body having the form of a saddle whose saddle surface is curved oppositely in the two principal directions, to a process for producing it, to its use in various catalytic gas phase oxidations, and to corresponding processes for catalytic gas phase oxidation.

Abstract: A process for producing a catalytically active composition being a mixture of a multielement oxide comprising the elements Mo and V and at least one oxide of molybdenum, in which spray drying of an aqueous solution or of an aqueous suspension of starting compounds comprising the elements of the multielement oxide produces a spray powder P, a pulverulent oxide of molybdenum and optionally shaping assistants are added thereto, shaped bodies are shaped from the resulting mixture and these are converted to the catalytically active composition by thermal treatment.

Abstract: An ?,?-unsaturated aldehyde and/or an ?,?-unsaturated carboxylic acid are prepared by gas phase oxidation of alkene with molecular oxygen over a fixed catalyst bed comprising a bed of hollow cylindrical shaped catalyst bodies having a multimetal oxide active composition. The fixed catalyst bed comprises at least three successive reaction zones; the highest local temperature in the fixed catalyst bed does not occur in the reaction zone closest to the reactor outlet; the highest local temperature in the fixed catalyst bed does not occur in the reaction zone closest to the reactor inlet; and the value WT=(ED?ID)/2 in the reaction zone in which the highest local temperature in the fixed catalyst bed occurs is lower than in the other reaction zones, in which ED is the external diameter and ID is the internal diameter of the shaped catalyst body. The yield of the products of value is enhanced in this way.

Abstract: A hollow cylindrical shaped catalyst body for gas phase oxidation of an alkene to an ?,?-unsaturated aldehyde and/or an ?,?-unsaturated carboxylic acid comprises a compacted multimetal oxide having an external diameter ED, an internal diameter ID and a height H, wherein ED is in the range from 3.5 to 4.5 mm; the ratio q=ID/ED is in the range from 0.4 to 0.55; and the ratio p=H/ED is in the range from 0.5 to 1. The shaped catalyst body is mechanically stable and catalyzes the partial oxidation of an alkene to the products of value with high selectivity. It provides a sufficiently high catalyst mass density of the catalyst bed and good long-term stability with acceptable pressure drop.

Abstract: What is described is a catalyst for preparation of an ?,?-unsaturated carboxylic acid by gas phase oxidation of an ?,?-unsaturated aldehyde, comprising a shaped support body with an active composition applied thereto, wherein the active composition coverage q q = Q ( 100 - Q ) ? S m is at most 0.3 mg/mm2, where Q is the active composition content of the catalyst in % by weight and Sm is the specific geometric surface area of the shaped support body in mm2/mg. Also described are a process for preparing the catalyst and a process for preparing an ?,?-unsaturated carboxylic acid by gas phase oxidation of an ?,?-unsaturated aldehyde over a fixed catalyst bed comprising a bed of the catalyst. The catalyst, with constantly high conversion of acrolein, reduces overoxidation to COx and increases the selectivity of acrylic acid formation.

Abstract: A process for producing a catalytically active composition being a mixture of a multielement oxide comprising the elements Mo and V and at least one oxide of molybdenum, in which spray drying of an aqueous solution or of an aqueous suspension of starting compounds comprising the elements of the multielement oxide produces a spray powder P, a pulverulent oxide of molybdenum and optionally shaping assistants are added thereto, shaped bodies are shaped from the resulting mixture and these are converted to the catalytically active composition by thermal treatment.

Abstract: A process for preparing (meth)acrylic acid by heterogeneously catalyzed gas phase partial oxidation of (meth)acrolein over a multimetal oxide composition which comprises the elements Mo, V and W and is obtained by a hydrothermal preparation route, and the multimetal oxide composition obtainable by this preparation route.

Abstract: This invention relates to a method for the preparation of a hydrocarbon synthesis catalyst material, in the form of a hydrocarbon synthesis catalyst precursor and/or catalyst, preferably, a Fischer Tropsch synthesis catalyst precursor and/or catalyst. The invention also extends to the use of a catalyst precursor and/or catalyst prepared by the method according to the invention in a hydrocarbon synthesis process, preferably, a Fischer Tropsch synthesis process. According to this invention, a method for the preparation of a hydrocarbon synthesis catalyst material includes the steps of treating Fe(II) carboxylate in solution with an oxidising agent to convert it to Fe(III) carboxylate in solution under conditions which ensure that such oxidation does not take place simultaneously with any dissolution of Fe(0); and hydrolysing the Fe(III) carboxylate solution resulting from step (iii) and precipitating one or more Fe(III) hydrolysis products.