Abstract: A reactor for gas-phase dehydrogenation of a hydrocarbon-comprising stream with an oxygen-comprising stream over a monolithic heterogeneous catalyst. Catalytically active zone(s) comprising monoliths packed next to one another and/or above one another and a mixing zone having fixed internals upstream of each catalytically active zone. Feed line(s) for the hydrocarbon-comprising gas stream to be dehydrogenated at the lower end of the reactor. Independently regulable feed line(s), which supply distributor(s), for the oxygen-comprising gas stream into each of the mixing zones and discharge line(s) for the reaction gas mixture of the autothermal gas-phase dehydrogenation at the upper end of the reactor. The interior wall of the reactor is provided with insulation. The catalytically active zone(s) is accessible from the outside of the reactor via manhole(s).

Abstract: The present invention relates to a process for preparing 1-adamantyltrimethylammonium hydroxide, by A) reacting 1-adamantyldimethylamine with dimethyl sulfate to give 1-adamantyltrimethylammonium sulfate; and B) subjecting the 1-adamantyltrimethylammonium sulfate obtained in A) to anion exchange with an ion exchanger loaded with OH ions.

Abstract: A reactor for gas-phase dehydrogenation of a hydrocarbon-comprising stream with an oxygen-comprising stream over a monolithic heterogeneous catalyst. Catalytically active zone(s) comprising monoliths packed next to one another and/or above one another and a mixing zone having fixed internals upstream of each catalytically active zone. Feed line(s) for the hydrocarbon-comprising gas stream to be dehydrogenated at the lower end of the reactor. Independently regulable feed line(s), which supply distributor(s), for the oxygen-comprising gas stream into each of the mixing zones and discharge line(s) for the reaction gas mixture of the autothermal gas-phase dehydrogenation at the upper end of the reactor. The interior wall of the reactor is provided with insulation. The catalytically active zone(s) is accessible from the outside of the reactor via manhole(s).

Abstract: Processes for decreasing fumaric acid deposits in preparing maleic anhydride by heterogeneously catalyzed oxidation of a hydrocarbon with molecular oxygen. Maleic anhydride is absorbed from the crude mixture in an absorbent in an absorption column and desorbed in a desorption column, the entirety or portion of absorbent depleted in maleic anhydride, for controlled precipitation of fumaric acid, being cooled and/or concentrated by evaporating a portion of absorbent such that the difference between the concentration of fumaric acid in the recycle stream at the outlet of the desorption column under existing conditions and the equilibrium concentration of fumaric acid according to the solubility curve after cooling and/or evaporation of a portion of absorbent is ?250 ppm by weight, and the fumaric acid precipitated as a solid is removed completely or partly from the absorbent recycling system and the fumaric acid-depleted absorbent is recycled completely or partly to the absorption column.

Abstract: In a process for preparing carboxylic esters by transesterification, a first feed stream comprising a first carboxylic ester, e.g. methyl formate, is introduced laterally into a reaction column at least one first feed point located between top and bottom of the reaction column and a second feed stream comprising a first alcohol, e.g. ethanol, is introduced laterally into the reaction column at a second feed point located above the first feed point and are reacted in a reaction zone of the reaction column to form a second carboxylic ester and a second alcohol. The first alcohol has a higher molecular weight than the second alcohol. A product fraction comprising the second carboxylic ester and unreacted first carboxylic ester is taken off at an offtake point located above the second feed point. At the bottom of the reaction column, a bottom fraction comprising the second alcohol and unreacted first alcohol is taken off.

Abstract: In a process for purifying carboxylic esters such as ethyl formate, a carboxylic ester to be purified is distilled in the presence of an extractant, preferably by (a) allowing vapor of the carboxylic ester to be purified to ascend in a distillation column; (b) conveying the extractant in countercurrent to the vapor in an extractive distillation column; (c) taking off pure carboxylic ester above the extractive distillation zone. The extractant is, for example, selected from among diols, polyols, open-chain or cyclic amides.

Abstract: The present invention relates to a process for preparing 1-adamantyltrimethyl-ammonium hydroxide.

Abstract: In a process for preparing carboxylic esters by transesterification, a first feed stream comprising a first carboxylic ester, e.g. methyl formate, is introduced laterally into a reaction column at least one first feed point located between top and bottom of the reaction column and a second feed stream comprising a first alcohol, e.g. ethanol, is introduced laterally into the reaction column at a second feed point located above the first feed point and are reacted in a reaction zone of the reaction column to form a second carboxylic ester and a second alcohol. The first alcohol has a higher molecular weight than the second alcohol. A product fraction comprising the second carboxylic ester and unreacted first carboxylic ester is taken off at an offtake point located above the second feed point. At the bottom of the reaction column, a bottom fraction comprising the second alcohol and unreacted first alcohol is taken off.

Abstract: In a process for purifying carboxylic esters such as ethyl formate, a carboxylic ester to be purified is distilled in the presence of an extractant, preferably by (a) allowing vapor of the carboxylic ester to be purified to ascend in a distillation column; (b) conveying the extractant in countercurrent to the vapor in an extractive distillation column; (c) taking off pure carboxylic ester above the extractive distillation zone. The extractant is, for example, selected from among diols, polyols, open-chain or cyclic amides.

Abstract: The present invention relates to a process for preparing tetrahydrofuran by absorption of C4-dicarboxylic acids and/or derivatives thereof from a crude product mixture into an organic solvent or water as absorption medium, removal of the absorption medium, catalytic hydrogenation of the resulting C4-dicarboxylic acids and/or derivatives thereof and distillation of the water-comprising crude tetrahydrofuran in at least one distillation column, wherein THF-comprising waste streams from the distillation are catalytically hydrogenated with complete or partial recirculation to the process.

Abstract: A process for decreasing fumaric acid deposits in the preparation of maleic anhydride by heterogeneously catalyzed oxidation of a hydrocarbon with molecular oxygen, in which the maleic anhydride is absorbed from the crude product mixture in an absorbent in an absorption column and desorbed again in a desorption column, the entirety or a portion of the absorbent depleted in maleic anhydride, for controlled precipitation of fumaric acid, being cooled and/or concentrated by evaporating a portion of the absorbent to such an extent that the difference between the concentration of fumaric acid in the recycle stream at the outlet of the desorption column under the conditions existing there and the equilibrium concentration of fumaric acid according to the solubility curve after the cooling and/or evaporation of a portion of the absorbent is greater than or equal to 250 ppm by weight, and the fumaric acid precipitated as a solid is removed completely or partly from the absorbent recycling system and the fumaric acid-

Abstract: The present invention relates to a process for preparing 3-alkoxypropan-1-ols of the general formula I by catalytic hydrogenation of esters of the general formula II, where the radicals R1 and R2 and R3, R4 and R5 are each, independently of one another, a straight-chain or branched C1-C20-alkyl radical which may optionally be substituted by one or more C1-C20-alkoxy radicals or interrupted by one or more oxygen atoms in the chain, C6-C20-aryl, C7-C20-arylalkyl which may optionally be substituted by one or more C1-C20-alkoxy radicals or interrupted by one or more oxygen atoms in the alkyl chain, C7-C20-alkylaryl which may optionally be substituted by one or more C1-C20-alkoxy radicals or interrupted by one or more oxygen atoms in the alkyl chain, a C1-C20-cycloalkyl radical which may optionally be substituted by one or more C1-C20-alkoxy radicals and R2, R3 and R4 can, independently of one another, also be hydrogen, over chromium- and nickel-free catalysts.

Abstract: The present invention provides a process for preventing fumaric acid deposits in the preparation of maleic anhydride, comprising the following steps: a) absorption of a C4-dicarboxylic acid or of a derivative from a crude product mixture into an organic solvent or water as an absorbent, b) removal of the C4-dicarboxylic acid or of a derivative from the absorbent, the absorbent thus recovered being catalytically hydrogenated fully or partly and recycled fully or partly into the absorption stage (a).

Abstract: Process for the preparation of ethylenamines, in particular diethylenetriamine (DETA), by continuous reaction of ethylenediamine (EDA) in the presence of a heterogeneous catalyst, where the reaction is carried out in a reaction column.

Abstract: Process for the preparation of ethylenamines, in particular diethylenetriamine (DETA), by continuous reaction of ethylenediamine (EDA) in the presence of a heterogeneous catalyst, where the reaction is carried out in a reaction column.

Abstract: A process for producing a catalytic converter utilizes deposition of a catalytically active material electrochemically deposited on a substrate as aresult of the substrate being immersed in an electrolyte, which contains the catalytically active material, and an electric voltage being applied between the substrate and a counterelectrode. The platinum is deposited on a metallic substrate from a platinum-containing sulphuric acid solution, or in which process a Pt/Ru mixture is deposited on a metallic substrate from a sulphuric acid solution containing platinum and ruthenium as catalytically active material, which a Pt:Ru ratio of from 1:10 to 1:20.