Abstract: A process for the preparation of an epoxide in the presence of a zeolite catalyst, in which

Abstract: A process for the regeneration of a zeolite catalyst which comprises treating the catalyst thermally in the presence of a gas stream at temperatures above 120° C., the weight-based residence time of the gas stream over the catalyst during the thermal treatment being greater than 2 hours.

Abstract: A process for regenerating a zeolite catalyst comprises thermal treatment of the catalyst at above 120° C. in the presence of a gas stream comprising hydrogen.

Abstract: A process for the preparation of propylene oxide in the presence of methanol, in which propylene oxide is separated from a mixture comprising propylene oxide and methanol, and the resultant mixture comprising methanol is worked up, which comprises separating methanol from a mixture comprising methanol and methyl formate during the work-up.

Abstract: A process for the preparation of propylene oxide in which

Abstract: In a continuous process for reacting an organic compound with hydroperoxide in the presence of a catalyst, the reaction is carried out in a reactor assembly comprising at least two reactors connected in parallel.

Abstract: A mixture (M1) comprising an alkene and oxygen is worked up by a process in which (i) oxygen is removed from the mixture (M1) by a nondistillative method to give a mixture (M2) and (ii) the alkene is separated off from the mixture (M2) by distillation.

Abstract: A process for the coproduction of 6-aminocapronitrile and hexamethylenediamine starting from adiponitrile by a) hydrogenating adiponitrile in the presence of a catalyst comprising an element of the eighth transition group as catalytically active component, to obtain a mixture comprising 6-aminocapronitrile, hexamethylenediamine, adiponitrile and high boilers, b) distillatively removing hexamethylenediamine from the mixture comprising 6-aminocapronitrile, hexamethylenediamine, adiponitrile and high boilers, and either cl) distillatively removing 6-aminocapronitrile, and then d1) distillatively removing adiponitrile, or c2) simultaneously distillatively removing 6-aminocapronitrile and adiponitrile into separate fractions is characterized by base of column temperatures below 185° C. in steps d1) or c2).

Abstract: A process for catalytic hydrogenation of adiponitrile to hexamethylenediamine at elevated temperature and elevated pressure in the presence of catalysts based on elemental iron as catalytically active component and ammonia as solvent comprises a) hydrogenating adiponitrile at from 70 to 220° C.

Abstract: A process for the coproduction of 6-aminocapronitrile and hexamethylenediamine starting from adiponitrile by a) hydrogenating adiponitrile in the presence of a catalyst comprising an element of the eighth transition group as catalytically active component, to obtain a mixture comprising 6-aminocapronitrile, hexamethylenediamine, adiponitrile and high boilers, b) distillatively removing hexamethylenediamine from the mixture comprising 6-aminocapronitrile, hexamethylenediamine, adiponitrile and high boilers, and either c1) distillatively removing 6-aminocapronitrile, and then d1) distillatively removing adiponitrile, or c2) simultaneously distillatively removing 6-aminocapronitrile and adiponitrile into separate fractions is characterized by base of column temperatures below 185° C. in steps d1) or c2).

Abstract: A process for distillative removal of part or all of an azepine derivative (III) selected from the group consisting of aminohexylideneimine, tetrahydroazepine, hexylhexahydroazepine and aminohexylhexahydroazepine from a mixture (II) comprising an azepine derivative (III) and an amine (I) comprises conducting the distillation with an overhead temperature of from 160 to 250° C.

Abstract: A material useful as catalyst for the hydrogenation of alpha, Omega-dinitriles comprises a) iron or a compound based on iron or mixtures thereof, (b) from 0.001 to 0.3% by weight based on (a) of a promoter based on 2, 3, 4 or 5 elements selected from the group consisting of aluminum, silicon, zirconium, titanium and vanadium, (c) from 0 to 0.3% by weight based on (a) of a compound based on an alkali and/or alkaline earth metal, and also (d) from 0.001 to 1% by weight based on (a) of manganese.

Abstract: A material useful as catalyst for the hydrogenation of alpha, omega-dinitriles comprises

Abstract: A process for preparing aliphatic alpha, omega-diamines by hydrogenation of aliphatic alpha, omega-dinitriles in the presence of a catalyst comprises using a hydrogenation catalyst comprising (a) iron or a compound based on iron or mixtures thereof, (b) from 0.001 to 0.3% by weight based on (a) of a promoter based on 2, 3, 4 or 5 elements selected from the group consisting of aluminum, silicon, zirconium, titanium and vanadium, and also (c) from 0 to 0.3% by weight based on (a) of a compound based on an alkali and/or alkaline earth metal.

Abstract: A process for hydrogenation of aliphatic alpha, omega-dinitriles in the presence of a heterogeneous fixed bed catalyst comprises using a reaction mixture comprising from 2 &mgr;mol to 30 mmol NA, K, Rb, Cs, Mg, Ca, Sr, Ba or Mn or mixtures thereof in the form of a basic salt, based on 10 mol of aliphatic alpha, omega-dinitrile used.

Abstract: A process for separating 2-aminomethylcyclopentylamine from a mixture consisting of hexamethylenediamine and 2-aminomethylcyclopentylamine by distilling the mixture at a pressure from 1 to 300 mbar.

Abstract: A process for distillative separation of part or all of an imine (III) from a mixture (II) comprising an amine (I) and said imine (III) comprises adding to the distillation mixture a compound (IV) which is inert toward said amine (I) under distillation conditions and whose boiling point is above the boiling point of said amine (I) under said distillation conditions to obtain, after the distillation, a mixture (VI) comprising essentially said compound (IV).

Abstract: A process for coproduction of 6-aminocapronitrile and hexamethylenediamine starting from adiponitrile comprises (1) partially hydrogenating adiponitrile in the presence of a catalyst to obtain a mixture comprising 6-aminocapronitrile, hexamethylenediamine and adiponitrile, (2) removing 6-aminocapronitrile and hexamethylenediamine from the mixture, (3) adding to the portion comprising essentially adiponitrile from 0.01 to 10% by weight of an acid, based on adiponitrile, or an acidic ion exchanger and removing the adiponitrile from the mixture, and (4) recycling the adiponitrile into step (1).

Abstract: A process for distillative removal of 6-aminocapronitrile from mixtures (I) comprising 6-aminocapronitrile and an imine (II) comprises conducting the distillation in the presence of carbon dioxide.

Abstract: A process for distillative removal of 6-aminocapronitrile from mixtures (I) comprising 6-aminocapronitrile and an imine (II) comprises performing the distillation in a distillation column using an average mean residence time for the distillation mixture of at least 5 minutes on at least one level of the distillation column.