摘要:
Process for the catalyzed reaction of an organic compound with a hydroperoxide in at least one reactor using at least two different zeolite catalysts, wherein at least two of the different zeolite catalysts are used physically separately from one another.
摘要:
The present invention provides a process for the epoxidation of propene which comprises reacting propene with hydrogen peroxide in the presence of methanol as solvent and a titanium zeolite catalyst, the process further comprising separating propylene oxide from the reaction mixture to obtain a mixture comprising methanol, water, at least one carboxylic acid and at least one carbonyl compound, wherein the at least one carboxylic acid is at least partially neutralized, said process optionally comprising a hydrogenation stage.
摘要:
A process is described for preparing 3-pentenenitrile, characterized by the following process steps: (a) isomerizing a reactant stream which comprises 2-methyl-3-butenenitrile over at least one dissolved or dispersed isomerization catalyst to give a stream 1 which comprises the at least one isomerization catalyst, 2-methyl-3-butenenitrile, 3-pentenenitrile and (Z)-2-methyl-2-butenenitrile, (b) distilling stream 1 to obtain a stream 2 as the top product which comprises 2-methyl-3-butenenitrile, 3-pentenenitrile and (Z)-2-methyl-2-butenenitrile, and a stream 3 as the bottom product which comprises the at least one isomerization catalyst, (c) distilling stream 2 to obtain a stream 4 as the top product which, compared to stream 2, is enriched in (Z)-2-methyl-2-butenenitrile, based on the sum of all pentenenitriles in stream 2, and a stream 5 as the bottom product which, compared to stream 2, is enriched in 3-pentenenitrile and 2-methyl-3-butenenitrile, based on the sum of all pentenenitriles in stream 2, (d) distilling stream 5 to obtain a stream 6 as the bottom product which comprises 3-pentenenitrile and a stream 7 as the top product which comprises 2-methyl-3-butenenitrile.
摘要:
Process for preparing propylene oxide, which comprises at least the steps (iii) and (iv) (iii) separating off propylene oxide from a mixture (M1) comprising propylene oxide and at least one solvent by distillation in a distillation column, giving a bottom stream and a vapor stream consisting essentially of propylene oxide; (iv) compressing the vapor stream obtained in (iii) by means of at least one compressor to give a compressed vapor.
摘要:
The invention relates to a continuously operated process for the purification by distillation of the 1,2-propylene glycol formed as by-product in the synthesis of propylene oxide, wherein the mixture formed in the synthesis which contains the 1,2-propylene glycol is separated in a dividing wall column into low-, intermediate- and high-boiling fractions and the 1,2-propylene glycol is taken off as intermediate boiler at the side offtake of the column.
摘要:
A process for removing high boilers from crude caprolactam which comprises high boilers, caprolactam and in some cases low boilers, and which has been obtained by a) reacting 6-aminocapronitrile with water to give a reaction mixture b) removing ammonia and unconverted water from the reaction mixture to obtain crude caprolactam, which comprises c) feeding the crude caprolactam to a distillation apparatus to obtain a first substream via the top as a product and a second substream via the bottom, by setting the pressure in the distillation in such a way that the bottom temperature does not go below 170° C., and adjusting the second substream in such a way that the caprolactam content of the second substream is not less than 10% by weight, based on the entire second substream.
摘要:
A process for separating a mixture comprising a) a monoolefinically unsaturated compound which is obtainable by adding two terminal olefins which bear the functional groups required to prepare the monoolefinically unsaturated compound containing at least two functional groups, or a saturated compound obtained by hydrogenating such a compound, b) a compound which is obtainable by adding more than two of the terminal olefins mentioned in a) or a compound obtained by hydrogenating such a compound, and c) a compound which contains a transition metal, is homogeneous with respect to the mixture and is suitable as a catalyst for preparing a monoolefinically unsaturated compound by adding two terminal olefins which bear the functional groups required to prepare the monoolefinically unsaturated compound containing at least two functional groups, by means of a semipermeable membrane to obtain a permeate and a retentate in such a way that the weight ratio of component b) to component c) in the mixture fed to the semipermeable membrane is smaller than in the retentate.
摘要:
Process for preparing an alkene oxide, which comprises at least the steps (i), (ii) and (v): (i) providing a stream S1 comprising compressed, liquid alkene; (ii) depressurizing at least part of the stream S1 with absorption of heat and with at least partial vaporization of the liquid alkene; (v) reacting the alkene obtained in (ii) with a hydroperoxide in the presence of at least one solvent and at least one catalyst to give a mixture comprising alkene oxide and the solvent or solvents.
摘要:
Process for the continuous recirculation of the olefin which has not been reacted in the oxidation of olefins by means of hydroperoxide to give oxiranes and is present in the offgas stream formed during the oxidation, which comprises the steps (i) to (iii) (i) separating the olefin from the offgas stream by absorption in a hydrocarbon, (ii) desorbing the olefin from the hydrocarbon, (iii) recirculating the olefin obtained in step (ii) to the oxidation process.
摘要:
Process for the continuously operated purification by distillation of the methanol used as solvent in the synthesis of propylene oxide by reaction of a hydroperoxide with propylene, with the methoxypropanols being separated off simultaneously, wherein the solvent mixture obtained in the synthesis is separated in a dividing wall column into a low-boiling fraction comprising methanol, an intermediate-boiling fraction comprising the methoxypropanols as azeotrope with water and a high-boiling fraction comprising water and propylene glycol.