Abstract: Lactams, in particular ?-caprolactam, are produced by the hydrolytic cyclization of aminonitriles, in particular 6-aminocapronitrile, in the vapor phase in a plurality of adiabatic fixed bed reaction zones arranged in succession wherein at least a portion of the heat of the exothermic reaction is removed between each of the successive reaction zones. Conducting the reaction in such a manner requires less capital for the reactor itself. It has also been found that the product exiting such a reaction system can be directly fed to a distillation unit without the need of additional cooling or storing.

Abstract: A method for recovering hexamethylene diamine (HMD) from a mixture comprising HMD, 6-aminocapronitrile (ACN) tetrahydroazepine (THA), and adiponitrile (ADN) is disclosed. The method includes introducing the mixture into a first distillation column, separating as a group the HMD, ACN and at least a portion of the THA as distillate from the ADN. The first distillation column is operated at a temperature and pressure to minimize isomerization of the ADN into 2-cyanocyclopentylideneimine(CPI). The distillate of the first distillation column is introduced into a subsequent distillation column and the HMD is separated from the ACN and THA.

Abstract: Method for making caprolactam from 6-aminocapronitrile that contains greater than 500 ppm tetrahydroazepine and its derivatives (THA) in which the THA is not removed from the method until after the caprolactam is produced.

Abstract: Method for making caprolactam from 6-aminocapronitrile that contains greater than 500 ppm tetrahydroazepine and its derivatives (THA) in which the THA is not removed from the method until after the caprolactam is produced.

Abstract: A method for recovering hexamethylene diamine (HMD) from a mixture comprising HMD, 6-aminocapronitrile (ACN) tetrahydroazepine (THA), and ADN comprising:

Abstract: Method for making caprolactam from 6-aminocapronitrile that contains greater than 500 ppm tetrahydroazepine and its derivatives (THA) in which ammonia and water are removed from crude caprolactam in a single separation step and then THA is removed from the resulting caprolactam melt.

Abstract: A method for separating a mixture of hexamethylenediamine, aminocapronitile and polarographically reducible impurities using fractional distillation in which the temperature in the rectifying zone of a distillation column varies sigmoidally along its length to force a major portion of the PRI to co-distill with the aminocapronitrile.

Abstract: 2-methylglutaronitrile and adiponitrile are purified by removal of boron residues by adding an alcohol or amino alcohol and then recovering the nitrile by distillation.

Abstract: Process for preparing a new compound: [hexakis(pentenenitrilo)nickel II]bis[.mu.-(cyano)bis(triphenylborane)(I)] which is useful as a promoter in the hydrocyanation of 3 or 4-pentenenitrile.

Abstract: Arylboranes are recovered from aqueous solutions of their basic adducts in improved yield by staged neutralization.

Abstract: An improved, continuous process for the preparation of hydrocyanation catalysts comprising zerovalent nickel complexes with organophosphorus compounds (ligands) by controlling the temperature of the reaction relative to the amount of ligand and conducting the reaction in the presence of a chlorine ion and organic nitrile such as adiponitrile.