Abstract: In a process for the preparation of alkylaromatic compounds by reacting C3-30-olefins, or alcohols from which C3-30-olefins are formed under the reaction conditions, with an aromatic hydrocarbon in the presence of an alkylation catalyst, the reaction is carried out in a reactor cascade of at least two reactors, where each of the reactors comprises the alkylation catalyst, at least 80% of the aromatic hydrocarbon are fed into the first reactor of the reactor cascade, and at least 40% of the olefins are intermediately fed in after the first reactor.

Abstract: Polyamides, oligomers thereof or mixtures thereof, if required with further reaction products, are prepared by reacting aminonitriles or dinitriles and diamines or a mixture containing aminonitrile, dinitrile and diamine, and, if required, further polyamide-forming monomers and/oligomers with water in a reactor (1) having a vertically oriented longitudinal axis, by a process in which, in the reactor (1), the reaction product is removed from the bottom and ammonia formed and any further low molecular weight compounds formed and water are taken off via the top (2), wherein the reactor (1) has at least two chambers (4) arranged one on top of the other in the longitudinal direction, the chambers (4) being separated from one another by liquid-tight trays (5), each chamber (4) being connected by a liquid overflow (6) to the chamber (4) directly underneath and a liquid product stream being taken off by the liquid overflow (6) of the lowermost chamber (4), the gas space (7) above the liquid level in each chambe

Abstract: A reactor (1) for gas/liquid or gas/liquid/solid reactions having a vertical longitudinal axis and an inlet (2) for a liquid or liquid/solid feed stream in the upper region of the reactor and an inlet (3) for a gaseous stream in the lower region of the reactor (1), wherein the gaseous stream (3) is conveyed through a gas distributor module (9) which is made up exclusively of straight tube sections (14, 15).

Abstract: In a process for the heterogeneously catalyzed dehydrogenation in one or more reaction zones of one or more dehydrogenatable C2-C30-hydrocarbons in a reaction gas mixture comprising them, with at least part of the heat of dehydrogenation required being generated directly in the reaction gas mixture in at least one reaction zone by combustion of hydrogen, the hydrocarbon or hydrocarbons and/or carbon in the presence of an oxygen-containing gas, the reaction gas mixture comprising the dehydrogenatable hydrocarbon or hydrocarbons is brought into contact with a Lewis-acid dehydrogenation catalyst which has essentially no Brönsted acidity.

Abstract: The present invention relates to a process for preparing polytetrahydrofuran, polytetrahydrofuran copolymer, diester or monoester by polymerizing tetrahydrofuran in the presence of at least one telogen and/or comonomer and of an acidic heterogeneous catalyst based on activated sheet silicates or mixed metal oxides in a fluidized bed.

Abstract: Amines are prepared by hydrogenation of the corresponding nitroaromatics in a vertical reactor whose length is greater than its diameter and which has in its upper region a downward-directed jet nozzle via which the reaction mixture and, if desired, part of the starting materials are introduced, has an outlet at any point on the reactor via which the reaction mixture is conveyed in an external circuit by means of a transport device back to the jet nozzle and has a flow reversal in its lower region, wherein at least part of the hydrogen and/or nitroaromatic starting materials used is fed into the liquid phase of the reactor in such a way that they travel upward in the liquid phase.

Abstract: The invention relates to a process for the preparation of methyl formate by reacting methanol with carbon monoxide at a pressure of from 0.5 to 10 MPa abs. and a temperature of from 50 to 150° C. in the presence of a metal alkoxide as catalyst in a reactor, in which a gas stream is withdrawn from the reactor, entrained methyl formate is removed from this gas stream by condensation, and all or some of the remaining gas stream is returned to the reactor as circulating-gas stream and a mean gas superficial velocity of from 1 to 20 cm/s is set in at least one region of the reactor in which the gas flows essentially in one direction.

Abstract: Olefins having at least 6 carbon atoms are hydroformylated in the presence of a homogeneous catalyst in a continuous process in which a) a vertical tall cylindrical reactor (1) whose interior space is divided by means of internals (2) into at least two reaction chambers which extend essentially in the longitudinal direction of the reactor is used, b) at least one olefin is introduced into the reactor together with synthesis gas at the lower end of the first reaction chamber, c) a partially reacted reaction mixture is conveyed from the upper end of a reaction chamber to the lower end of a next reaction chamber; and d) the hydroformylated olefin is taken off at the upper end of the last reaction chamber. The process allows a high conversion at a given reactor volume.

Abstract: Formic acid and a carboxylic acid having at least two carbon atoms and/or derivatives thereof are prepared jointly by a process in which (a) a formic ester (I) is transesterified with a carboxylic acid having at least two carbon atoms (II) to form formic acid (III) and the corresponding carboxylic ester (IV); and (b) at least part of the carboxylic ester (IV) formed in step (a) is carbonylated to give the corresponding carboxylic anhydride (V).

Abstract: In a process for reducing the formation of polymers during side-chain alkylation or side-chain alkenylation of alkylaromatic compounds by reaction with olefins or diolefins in the presence of an alkali metal catalyst followed by distillation in order to isolate the alkylated or alkenylated compound, the alkali metal is present in the catalyst on an inorganic support, and the catalyst is mechanically separated from the reaction mixture after the reaction and before the distillation.

Abstract: Olefins having at least 6 carbon atoms are hydroformylated in the presence of a homogeneous catalyst in a continuous process in which a) a vertical tall cylindrical reactor (1) whose interior space is divided by means of internals (2) into at least two reaction chambers which extend essentially in the longitudinal direction of the reactor is used, b) at least one olefin is introduced into the reactor together with synthesis gas at the lower end of the first reaction chamber, c) a partially reacted reaction mixture is conveyed from the upper end of a reaction chamber to the lower end of a next reaction chamber; and d) the hydroformylated olefin is taken off at the upper end of the last reaction chamber. The process allows a high conversion at a given reactor volume.

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: The invention relates to a process for the preparation of methyl formate by reacting methanol with carbon monoxide at a pressure of from 0.5 to 10 MPa abs. and a temperature of from 50 to 150° C. in the presence of a metal alkoxide as catalyst in a reactor, in which a gas stream is withdrawn from the reactor, entrained methyl formate is removed from this gas stream by condensation, and all or some of the remaining gas stream is returned to the reactor as circulating-gas stream and a mean gas superficial velocity of from 1 to 20 cm/s is set in at least one region of the reactor in which the gas flows essentially in one direction.

Abstract: Amines are prepared by hydrogenation of the corresponding nitroaromatics in a vertical reactor whose length is greater than its diameter and which has in its upper region a downward-directed jet nozzle via which the reaction mixture and, if desired, part of the starting materials are introduced, has an outlet at any point on the reactor via which the reaction mixture is conveyed in an external circuit by means of a transport device back to the jet nozzle and has a flow reversal in its lower region, wherein at least part of the hydrogen and/or nitroaromatic starting materials used is fed into the liquid phase of the reactor in such a way that they travel upward in the liquid phase.

Abstract: A process for the continuous heterogeneously catalyzed partial dehydrogenation of a hydrocarbon in the gas phase and in the presence of molecular oxygen, in which part of the product gas is recirculated to the reaction zone, and a reactor for carrying out such a process.

Abstract: Liquid organic compounds are hydrogenated by a process in which the hydrogen present in the reactor contains proportions of at least one gas which is inert in the hydrogenation reaction.

Abstract: In a process for preparing essentially unbranched oligomers of alkenes having from 4 to 6 carbon atoms starting from the alkenes or a hydrocarbon stream comprising such alkenes over a nickel-containing heterogeneous catalyst in an adiabatically operated reactor at from 20 to 300° C. and pressures of from 1 to 100 bar, a first substream of the output from the reactor is worked up to isolate the oligomers and the second substream is recirculated together with fresh alkene or a fresh hydrocarbon stream comprising such alkenes to the reactor.

Abstract: A reactor (1) for gas/liquid or gas/liquid/solid reactions having a vertical longitudinal axis and an inlet (2) for a liquid or liquid/solid feed stream in the upper region of the reactor and an inlet (3) for a gaseous stream in the lower region of the reactor (1), wherein the gaseous stream (3) is conveyed through a gas distributor module (9) which is made up exclusively of straight tube sections (14, 15).

Abstract: A reactor (1) of high cylindrical construction for continuously carrying out gas-liquid, liquid-liquid or gas-liquid-solid reactions, provided with a downward-directed jet nozzle (2) via which the starting materials and the reaction mixture are fed in and which is located in the upper region of the reactor, and provided with an offtake (3), preferably in the lower region of the reactor, via which the reaction mixture is conveyed via an external circuit back to the jet nozzle (2) by means of a pump (P), wherein a guide tube (4) which extends essentially over the total length of the reactor (1) with the exception of the reactor ends and has a cross-sectional area in the range from one tenth to one half of the cross-sectional area of the reactor (1) is located concentrically in the reactor (1), and the jet nozzle (2) is located above the upper end of the guide tube (4), preferably at a distance of from one eighth of the guide tube diameter to one guide tube diameter, or projects into the guide tube (4) to a dept

Abstract: Formic acid and a carboxylic acid having at least two carbon atoms and/or derivatives thereof are prepared jointly by a process in which