摘要:
A process for preparing caprolactam by cyclization of 6-aminocapronitrile in the presence of water at elevated temperature and in the presence or absence of a catalyst and a solvent, comprises a) removing from the cyclization reaction effluent ("reaction effluent I") caprolactam and all components boiling higher than caprolactam ("high boilers"), b) treating the high boilers of stage a) with phosphoric acid and/or polyphosphoric acid at from 200 to 350.degree. C. to obtain a reaction effluent II, and c) removing caprolactam formed and any 6-aminocapronitrile from reaction effluent II of stage b) to obtain separation from unconverted high boilers and acid used.
摘要:
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.
摘要:
A process for recovering hexamethylenediamine (I) from a mixture (II) including(I) hexamethylenediamine,(III) hexamethyleneimine,(IV) a compound selected from 2-aminomethylcyclopentylamine and 1,2-diaminocyclohexane,(V) an imine,(VI) adiponitrile and 6-aminocapronitrileincludes distilling(a) a mixture (II) to obtain(a1) a low boiling fraction (III),(a2) a medium boiling fraction (VII) (I), (IV) and (V), and(a3) a high boiling fraction (V) and (VI),(b) a mixture (VII) to obtain(b1) an overhead product (IV), and(b2) a mixture (VIII) (I) and (V) as bottom product, and(c) a mixture (VIII) to obtain(c1) (I) as overhead product, and(c2) a bottom product (V).
摘要:
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. and from 100 to 400 bar in the presence of catalysts based on elemental iron as catalytically active component and ammonia as solvent to obtain a mixture comprising adiponitrile, 6-aminocapronitrile, hexamethylenediamine and high boilers until the sum total of the 6-aminocapronitrile concentration and the adiponitrile concentration is within the range from 1 to 50% by weight, based on the ammonia-free hydrogenation mixture, b) removing ammonia from the hydrogenation effluent, c) removing hexamethylenediamine from the remaining mixture, d) separating 6-aminocapronitrile and adiponitrile from high boilers individually or together, and e) returning 6-aminocapronitrile, adiponitrile or mixtures thereof into step a).
摘要:
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).
摘要:
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.
摘要:
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.
摘要:
The level of an unsaturated cyclic imine (I) of the formula (I) where R1 is alkenyl having 3, 4, 5, 6, 7, 8, 9, 10, 11 carbon atoms belonging to the ring system, in a mixture comprising hexamethylenediamine and an imine (I) is reduced by electrochemical conversion of an imine (I) in a mixture comprising hexamethylenediamine and an imine (I) in the presence of solvated protons into a saturated cyclic amine of the formula (II)
摘要:
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).