Abstract: The invention relates to a shaped catalyst body in the form of a tetralobe having four outer through-passages and a ratio of diameter to height of the shaped body of from 0.25 to 1.0 and having a central fifth through-passage. It is used for the oxidation of S02 to S03.

Abstract: The present invention relates to a catalyst system for oxidation of o-xylene and/or naphthalene to phthalic anhydride (PA) comprising at least four catalyst zones arranged in succession in the reaction tube and filled with catalysts of different chemical composition wherein the active material of the catalysts comprise vanadium and titanium dioxide and the active material of the catalyst in the last catalyst zone towards the reactor outlet has an antimony content (calculated as antimony trioxide) between 0.7 to 3.0 wt. %.

Abstract: Multimetal oxide composition comprising Mo, Bi, Fe, Cu and one or more than one of the elements Co and Ni and use thereof.

Abstract: The invention relates to a process for preparing butadiene from n-butenes in n reactors R1 to Rn operated in parallel, wherein the process in the production phase of a reactor Rm in the n reactors comprises the steps: A) provision of a feed gas stream a1m comprising n-butenes; B) feeding of the feed gas stream a1m comprising n-butenes, an oxygen-comprising gas stream a2m and a substream d2m of an oxygen-comprising total recycle gas stream d2 into the oxidative dehydrogenation zone of the reactor and oxidative dehydrogenation of n-butenes to butadiene, giving a product gas substream bm comprising butadiene; C) combination of the product gas substream bm with further product gas substreams to form a total product gas stream b and cooling and compression of the total product gas stream b and condensation of at least part of the high-boiling secondary components, giving at least one aqueous condensate stream c1 and a gas stream c2 comprising butadiene; D) feeding of the gas stream c2 into an absorption zone an

Abstract: Process for preparing butadiene from n-butenes, which has a start-up phase and an operating phase and the operating phase of the process comprises the steps: A) provision of a feed gas stream a1 comprising n-butenes; B) introduction of the feed gas stream a1 comprising n-butenes, an oxygen-comprising gas stream a2 and an oxygen-comprising recycle gas stream d2 into at least one oxidative dehydrogenation zone and oxidative dehydrogenation of n-butenes to butadiene, giving a product gas stream b comprising butadiene; C) cooling and compression of the product gas stream b, giving at least one aqueous condensate stream c1 and a gas stream c2 comprising butadiene; D) introduction of the gas stream c2 into an absorption zone and separation of incondensable and low-boiling gas constituents as gas stream d from the gas stream c2 by absorption of the C4 hydrocarbons in an absorption medium, giving an absorption medium stream loaded with C4 hydrocarbons and the gas stream d, and recirculation of the gas stream d as re

Abstract: The invention relates to a process for producing butadiene from n-butenes which comprises the steps of: A) providing a vaporous n-butenes-comprising input gas stream a1 by evaporating a liquid n-butenes-comprising stream a0; B) introducing the vaporous n-butenes-comprising input gas stream a1 and an at least oxygenous gas into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene to obtain a product gas stream b comprising butadiene, unconverted n-butenes, steam, oxygen, low-boiling hydrocarbons, high-boiling secondary components, possibly carbon oxides and possibly inert gases, Ca) chilling the product gas stream b by contacting with a cooling medium comprising an organic solvent in at least one chilling zone, the cooling medium being at least partially recycled into the chilling zone, Cb) compressing the chilled product gas stream b which is possibly depleted of high-boiling secondary components in at least one compression stage to obtain at least one aqueous c

Abstract: The invention relates to a process for preparing 1,3-butadiene from n-butenes, comprising the steps of: A) providing an input gas stream a comprising butanes, 1-butene, 2-butene and isobutene, with or without 1,3-butadiene, from a fluid catalytic cracking plant; B) removing isobutene from the input gas stream a, giving a stream b comprising butanes, 1-butene and 2-butene, with or without 1,3-butadiene; C) feeding the stream b comprising butanes, 1-butene and 2-butene and optionally an, oxygenous gas and optionally water vapor into at least one dehydrogenating zone and dehydrogenating 1-butene and 2-butene to 1,3-butadiene, giving a product gas stream c comprising 1,3-butadiene, butanes, 2-butene and water vapor, with or without oxygen, with low-boiling hydrocarbons, with high-boiling secondary components, with or without carbon oxides and with or without inert gases; D) cooling and compressing the product gas stream c, giving at least one aqueous condensate stream d1 and a gas stream d2 comprising 1,3-buta

Abstract: Multimetal oxide composition comprising Mo, Bi, Fe, Cu and one or more than one of the elements Co and Ni and use thereof.

Abstract: A process for preparing butadiene from n-butenes, comprising the steps of: A) providing an input gas stream comprising n-butenes; B) feeding the input gas stream comprising n-butenes and a gas containing at least oxygen into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene, giving a product gas stream; Ca) cooling the product gas stream by contacting with a circulating cooling medium in at least one cooling zone; Cb) compressing the cooled product gas stream in at least one compression stage, giving at least one aqueous condensate stream c1 and one gas stream c2; D) removing uncondensable and low-boiling gas constituents comprising oxygen and low-boiling hydrocarbons as gas stream d2 from the gas stream c2 by absorbing the C4 hydrocarbons in an absorbent, giving an absorbent stream laden with C4 hydrocarbons and the gas stream d2, and then desorbing the C4 hydrocarbons from the laden absorbent stream, giving a C4 product gas stream d1; E) separating the C4

Abstract: The invention relates to shaped catalyst bodies for the oxidation of SO2 to SO3, which comprise vanadium, at least one alkali metal and sulfate on a silicon dioxide support material, wherein the shaped body has the shape of a cylinder having 3 or 4 hollow-cylindrical convexities, obtainable by extrusion of a catalyst precursor composition comprising vanadium, at least one alkali metal and sulfate on a silicon dioxide support material through the opening of an extrusion tool, wherein the opening of the extrusion tool has a cross section formed by 3 or 4 partly overlapping rings whose midpoints lie essentially on a circular line having a diameter of y, wherein the rings are bounded by an outer line lying on a circle having an external diameter x1 and an inner line lying on a circle having an internal diameter x2.

Abstract: The invention relates to a process for preparing 1,3-butadiene from n-butenes, comprising the steps of: A) providing an input gas stream a comprising butanes, 1-butene, 2-butene and isobutene, with or without 1,3-butadiene, from a fluid catalytic cracking plant; B) removing isobutene from the input gas stream a, giving a stream b comprising butanes, 1-butene and 2-butene, with or without 1,3-butadiene; C) feeding the stream b comprising butanes, 1-butene and 2-butene and optionally an, oxygenous gas and optionally water vapor into at least one dehydrogenating zone and dehydrogenating 1-butene and 2-butene to 1,3-butadiene, giving a product gas stream c comprising 1,3-butadiene, butanes, 2-butene and water vapor, with or without oxygen, with low-boiling hydrocarbons, with high-boiling secondary components, with or without carbon oxides and with or without inert gases; D) cooling and compressing the product gas stream c, giving at least one aqueous condensate stream d1 and a gas stream d2 comprising 1,3-buta

Abstract: Process for producing a multimetal oxide catalyst comprising molybdenum, chromium and at least one further metal by mixing of a pulverulent multimetal oxide comprising molybdenum and at least one further metal but no chromium with pulverulent chromium(III) oxide and thermal treatment of the resulting pulverulent mixture in the presence of oxygen at a temperature in the range from 350° C. to 650° C.

Abstract: A process for preparing butadiene from n-butenes, comprising the steps of: absorbing C4 hydrocarbons comprising butadiene and n-butenes, obtained from oxidative dehydrogenation of n-butenes, in an aromatic hydrocarbon solvent as an absorbent and removing uncondensable and low-boiling gas constituents comprising oxygen, low-boiling hydrocarbons, any carbon oxides, aromatic hydrocarbon solvent and any inert gases as gas stream d2, giving an absorbent stream laden with C4 hydrocarbons and the gas stream d2, and then desorbing the C4 hydrocarbons from the laden absorbent stream, giving a C4 product gas stream d1; and at least partly recycling the gas stream d2 as cycle gas stream a2 into the oxidative dehydrogenation zone, wherein the content of aromatic hydrocarbon solvent in the cycle gas stream a2 is limited to less than 1% by volume.

Abstract: The invention relates to a process for preparing butadiene from n-butenes, comprising the steps of: A) providing an input gas stream a comprising n-butenes, B) feeding the input gas stream a comprising n-butenes and a gas containing at least oxygen into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene, giving a product gas stream b comprising butadiene, unconverted n-butenes, water vapor, oxygen, low-boiling hydrocarbons and high-boiling secondary components, with or without carbon oxides and with or without inert gases; Ca) cooling the product gas stream b by contacting with a cooling medium in at least one cooling zone, the cooling medium being at least partly recycled and having an aqueous phase and an organic phase of an organic solvent, wherein the organic solvent is selected from the group consisting of toluene, o-, m- and p-xylene, mesitylene, mono-, di- and triethylbenzene, mono-, di- and triisopropylbenzene and mixtures thereof, and the mass ratio of

Abstract: The invention relates to shaped catalyst bodies for the oxidation of SO2 to SO3, which comprise vanadium, at least one alkali metal and sulfate on a silicon dioxide support material, wherein the shaped body has the shape of a cylinder having 3 or 4 hollow-cylindrical convexities, obtainable by extrusion of a catalyst precursor composition comprising vanadium, at least one alkali metal and sulfate on a silicon dioxide support material through the opening of an extrusion tool, wherein the opening of the extrusion tool has a cross section formed by 3 or 4 partly overlapping rings whose midpoints lie essentially on a circular line having a diameter of y, wherein the rings are bounded by an outer line lying on a circle having an external diameter x1 and an inner line lying on a circle having an internal diameter x2.

Abstract: The invention relates to a process for producing butadiene from n-butenes which comprises the steps of: A) providing a vaporous n-butenes-comprising input gas stream a1 by evaporating a liquid n-butenes-comprising stream a0; B) introducing the vaporous n-butenes-comprising input gas stream a1 and an at least oxygenous gas into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene to obtain a product gas stream b comprising butadiene, unconverted n-butenes, steam, oxygen, low-boiling hydrocarbons, high-boiling secondary components, possibly carbon oxides and possibly inert gases, Ca) chilling the product gas stream b by contacting with a cooling medium comprising an organic solvent in at least one chilling zone, the cooling medium being at least partially recycled into the chilling zone, Cb) compressing the chilled product gas stream b which is possibly depleted of high-boiling secondary components in at least one compression stage to obtain at least one aqueous c

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: The present invention relates to a catalyst system for oxidation of o-xylene and/or naphthalene to phthalic anhydride (PA), comprising a plurality of catalyst zones arranged in succession in the reaction tube, which has been produced using antimony trioxide consisting predominantly of the senarmontite modification of which all primary crystallites have a size of less than 200 nm. The present invention further relates to a process for gas phase oxidation, in which a gas stream comprising at least one hydrocarbon and molecular oxygen is passed through a catalyst system which comprises a plurality of catalyst zones arranged in succession in the reaction tube and which has been produced using an antimony trioxide consisting predominantly of the senarmontite modification with a median primary crystallite size of less than 200 nm.

Abstract: The present invention relates to a catalyst system for oxidation of o-xylene and/or naphthalene to phthalic anhydride (PA) comprising at least four catalyst zones arranged in succession in the reaction tube and filled with catalysts of different chemical composition wherein the active material of the catalysts comprise vanadium and titanium dioxide and the active material of the catalyst in the last catalyst zone towards the reactor outlet has an antimony content (calculated as antimony trioxide) between 0.7 to 3.0 wt. %.

Abstract: A process for preparing butadiene from n-butenes, comprising the steps of: A) providing an input gas stream comprising n-butenes; B) feeding the input gas stream comprising n-butenes and a gas containing at least oxygen into at least one oxidative dehydrogenation zone and oxidatively dehydrogenating n-butenes to butadiene, giving a product gas stream; Ca) cooling the product gas stream by contacting with a circulating cooling medium in at least one cooling zone; Cb) compressing the cooled product gas stream in at least one compression stage, giving at least one aqueous condensate stream c1 and one gas stream c2; D) removing uncondensable and low-boiling gas constituents comprising oxygen and low-boiling hydrocarbons as gas stream d2 from the gas stream c2 by absorbing the C4 hydrocarbons in an absorbent, giving an absorbent stream laden with C4 hydrocarbons and the gas stream d2, and then desorbing the C4 hydrocarbons from the laden absorbent stream, giving a C4 product gas stream d1; E) separating the C4