Abstract: The invention relates to a process for preparing butadiene from n-butane having the steps of A) providing a feed gas stream a comprising n-butane; B) feeding the feed gas stream a comprising n-butane into at least one first dehydrogenation zone and nonoxidatively catalytically dehydrogenating n-butane to obtain a product gas stream b comprising n-butane, 1-butene, 2-butene, butadiene, hydrogen, low-boiling secondary constituents and in some cases steam; C) feeding the product gas stream b of the nonoxidative catalytic dehydrogenation and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating 1-butene and 2-butene to obtain a product gas stream c comprising n-butane, 2-butene, butadiene, hydrogen, low-boiling secondary constituents and steam, said product gas stream c having a higher content of butadiene than the product gas stream b; D) removing hydrogen, the low-boiling secondary constituents and steam to obtain a C4 product gas stream d substantially consisting of

Abstract: A) Provision of an n-butane-containing feed gas stream a; B) introduction of the n-butane-containing feed gas stream a into at least one dehydrogenation zone and nonoxidative catalytic dehydrogenation of n-butane to give a product gas stream b comprising n-butane, 1-butene, 2-butene, butadiene, low-boiling secondary constituents, hydrogen and possibly water vapor, C) removal of hydrogen, the low-boiling secondary constituents and, if appropriate, water vapor to give a C4 product gas stream c consisting essentially of n-butane, 1-butene, 2-butene and butadiene; D) introduction of the C4 product gas stream c consisting essentially of n-butane, 1-butene, 2-butene and butadiene into a selective hydrogenation zone and selective hydrogenation of butadiene to 1- and/or 2-butene to give a stream d consisting essentially of n-butane, 1-butene and 2-butene; E) separation of the stream d into a desired product stream e1 consisting essentially of 1-butene and a recycle stream e2 consisting essentially of 2-butene and n

Abstract: The invention relates to a process for preparing butadiene from n-butane having the steps of A) providing a feed gas stream a comprising n-butane; B) feeding the feed gas stream a comprising n-butane into at least one first dehydrogenation zone and nonoxidatively catalytically dehydrogenating n-butane to obtain a product gas stream b comprising n-butane, 1-butene, 2-butene, butadiene, hydrogen, low-boiling secondary constituents and in some cases steam; C) feeding the product gas stream b of the nonoxidative catalytic dehydrogenation and an oxygenous gas into at least one second dehydrogenation zone and oxidatively dehydrogenating n-butane, 1-butene and 2-butene to obtain a product gas stream c comprising n-butane, 2-butene, butadiene, low-boiling secondary constituents and steam, said product gas stream c having a higher content of butadiene than the product gas stream b; D) removing the low-boiling secondary constituents and steam to obtain a C4 product gas stream d substantially consisting of n-butane, 2-

Abstract: Process for preparing at least one partial oxidation and/or ammoxidation product of propylene, in which the propylene is produced from crude propane by dehydrogenation and is subjected to a heterogeneously catalyzed gas-phase partial oxidation and/or partial gas-phase ammoxidation in the presence of unreacted propane as constituent of a gas mixture 2 containing <1% by volume of 1-butene.

Abstract: A process for continuous heterogeneously catalyzed partial dehydrogenation of at least one hydrocarbon to be dehydrogenated in a reactor which is manufactured from a steel with specific elemental composition on its side in contact with the reaction gas, and also partial oxidations of the dehydrogenated hydrocarbon and the reactor itself.

Abstract: A process for stably operating a continuous preparation process for obtaining acrolein or acrylic acid or a mixture thereof from propane, in which the feed rate of fresh propane to the process is utilized as a correcting element for stable steady-state operation.

Abstract: Catalyst supports and catalysts comprising them, having a certain tortuosity, and their use for heterogeneously catalyzed dehydrogenations of hydrocarbons.

Abstract: A process for preparing acrolein or acrylic acid or a mixture thereof from propane, in which propane is dehydrogenated under heterogeneous catalysis in a reaction zone A and the propylene formed is partially oxidized heterogeneously in a reaction zone, reaction zone A being operated in loop mode and reaction gas mixture input stream A fed to the reaction zone A comprising added molecular hydrogen which is added to this input stream as late as possible.

Abstract: The invention relates to a process for preparing 4-vinylcyclohexene, which comprises the steps (A) providing an n-butane-containing feed gas stream, (B) feeding the n-butane-containing feed gas stream into at least one dehydrogenation zone and dehydrogenating n-butane to butadiene to give a product stream comprising butadiene, n-butane, possibly 1-butene and 2-butene and possibly water vapor and other secondary constituents, (C) feeding the product stream from dehydrogenation, if appropriate after separating off water vapor and secondary constituents, into a dimerization zone and catalytically dimerizing butadiene to give a product stream comprising 4-vinylcyclohexene, n-butane and possibly 1-butene, 2-butene and unreacted butadiene, and (D) separating off 4-vinylcyclohexene from the product stream from the dimerization and recirculating n-butane and possibly 1-butene, 2-butene and unreacted butadiene to the dehydrogenation zone.

Abstract: A) Provision of an n-butane-containing feed gas stream a; B) introduction of the n-butane-containing feed gas stream a into at least one dehydrogenation zone and nonoxidative catalytic dehydrogenation of n-butane to give a product gas stream b comprising n-butane, 1-butene, 2-butene, butadiene, hydrogen, low-boiling secondary constituents and possibly water vapor; C) removal of hydrogen, the low-boiling secondary constituents and, if appropriate, water vapor to give a C4 product gas stream c consisting essentially of n-butane, 1-butene, 2-butene and butadiene; D) separation of the C4 product gas stream c into a recycle stream d1 consisting essentially of n-butane and a stream d2 comprising 1-butene, 2-butene and butadiene by extractive distillation and recirculation of the recycle stream d1 consisting essentially of n-butane to the dehydrogenation zone; E) introduction of the stream d2 comprising 1-butene, 2-butene and butadiene into a selective hydrogenation zone and selective hydrogenation of butadiene to

Abstract: Process for preparing alpha, beta-unsaturated acyclic or cyclic carbonyl compounds by dehydrogenation of the corresponding saturated carbonyl compounds in the gas phase over a heterogeneous dehydrogenation catalyst comprising platinum and/or palladium and tin on an oxidic support.

Abstract: The present invention relates to a process for producing propylene oxide comprising (I) reacting propene with hydrogen peroxide in the presence of a catalyst to give a mixture (GI) comprising propylene oxide, unreacted propene, and oxygen; (II) separating propylene oxide from mixture (GI) to give a mixture (GII) comprising propene and oxygen; (III) reducing the oxygen comprised in mixture (GII) at least partially by reaction with hydrogen in the presence of a catalyst comprising Sn and at least one noble metal.

Abstract: Process for preparing saturated aliphatic Cn-aldehydes and Cn-1-alkanes, where n is from 4 to 20, which comprises a) providing a feed gas stream comprising one or more Cn-1-alkanes, b) subjecting the Cn-1-alkanes to a catalytic dehydrogenation to give a product gas stream comprising unreacted Cn-1-alkanes, one or more Cn-1-alkenes and secondary constituents, c) at least partly hydroformylating the Cn-1-alkenes in the presence of the Cn-1-alkanes and possibly the secondary constituents by means of carbon monoxide and hydrogen in the presence of a hydroformylation catalyst to give the Cn-aldehydes, d) separating the product mixture obtained to give a stream comprising the Cn-aldehydes and a stream comprising Cn-1-alkanes and possibly secondary constituents, e) recirculating at least part of the gas stream comprising the Cn-1-alkanes and possibly the secondary constituents as recycle gas stream to the catalytic alkane dehydrogenation (step b)).

Abstract: C2–C30-alkanes are dehydrogenated in a process in which (i) ethylbenzene is dehydrogenated to styrene in a first part process to give a hydrogen-containing offgas stream, and (ii) one or more C2–C30-alkanes are dehydrogenated in the presence of a heterogeneous catalyst in one or more reaction zones in a second part process to give the corresponding olefins, with a hydrogen-containing gas stream being mixed into the reaction gas mixture of the dehydrogenation in at least one reaction zone, wherein at least part of the hydrogen-containing offgas stream obtained in the dehydrogenation of ethylbenzene is mixed into the reaction gas mixture of the alkane dehydrogenation.

Abstract: The invention relates to a process for preparing butadiene from n-butane comprising the steps (A) providing an n-butane-containing feed gas stream, (B) feeding the n-butane-containing feed gas stream into a first dehydrogenation zone and nonoxidatively catalytically dehydrogenating n-butane to 1-butene, 2-butene and optionally butadiene to obtain a first product gas stream comprising n-butane, 1-butene and 2-butene, with or without butadiene and secondary components, (C) feeding the first product gas stream comprising n-butane, 1-butene and 2-butene, with or without butadiene and secondary components, into a second dehydrogenation zone and oxidatively dehydrogenating 1-butene and 2-butene to butadiene to give a second product gas stream comprising butadiene, n-butane and steam, with or without secondary components, (D) recovering butadiene from the second product gas stream.

Abstract: The invention relates to a process for preparing a catalyst support, in which zirconium dioxide powder is mixed with a binder, if desired a pore former, if desired an acid, water and, if desired, further additives to give a kneadable composition and the composition is homogenized, shaped to produce shaped bodies, dried and calcined, wherein the binder is a monomeric, oligomeric or polymeric organosilicon compound. Suitable binders are monomeric, oligomeric or polymeric silanes, alkoxysilanes, aryloxysilanes, acryloxysilanes, oximinosilanes, halosilanes, aminoxysilanes, aminosilanes, amidosilanes, silazanes or silicones. The invention also provides the catalyst support which has been prepared in this way, a catalyst comprising the support and its use as dehydrogenation catalyst.

Abstract: A process for preparing acrolein or acrylic acid or a mixture thereof from propane, in which the propane is initially dehydrogenated under heterogeneous catalysis to give propene, secondary components are removed and the remaining gas mixture, comprising propane and propene, is subjected to the heterogeneously catalyzed partial oxidation to acrolein or acrylic acid or a mixture thereof as the target product, target product is removed from the product gas mixture and the remaining residual gas, comprising excess oxygen and unconverted propane, is recycled into the propane dehydrogenation in such a way that the other propane fed to the dehydrogenation is at least partly converted under dehydrogenating conditions at the recycle point.

Abstract: The present invention relates to an integrated process for the synthesis of propylene oxide, which comprises at least the following steps: (i) dehydrogenation of propane to give a substream T (0) comprising at least propane, propene and hydrogen; (ii) fractionation of the substream T (0) to give at least one gaseous hydrogen-rich substream T (2) and a substream T (1) comprising at least propene and propane; (iii) synthesis of hydrogen peroxide using the substream T (2), giving a substream T (4) which is rich in hydrogen peroxide and a gaseous substream T (6); (iv) fractionation of the substream T (1) to give at least one propane-rich substream T (5) and at least one propene-rich substream T (3); (v) reaction of the at least one substream T (3) with substream T (4) to give propylene oxide.

Abstract: A process prepares methacrylic acid from isobutane by subjecting isobutane to a partial catalytic dehydrogenation in the gas phase and charging an oxidation zone with the isobutenic product gas mixture after the components other than isobutane and isobutene have been substantially removed from the product gas mixture. The oxygen required to charge the oxidation zone is introduced accompanied by nitrogen.

Abstract: A process for preparing alkenylaromatic compounds by reacting alkylaromatic compounds in the presence of steam and natural gas or methane over a suitable catalyst at a temperature of from 400 to 800° C. and a pressure of from 0.01 to 10 bar, wherein the molar ratio of steam to alkylaromatic compound is from 6.9:1 to 1:1 or the molar ratio of methane to alkylaromatic compound is from 0.1:1 to 8:1.