Abstract: A process is described for separating mixtures of isomeric pentenenitriles, in which at least one isomer is removed from the mixture, wherein the separation of the substance mixtures of isomeric pentenenitriles is effected distillatively under reduced pressure.

Abstract: A process is described for separating mixtures of isomeric pentenenitriles, in which at least one isomer is removed from the mixture, wherein the separation of the substance mixtures of isomeric pentenenitriles is effected distillatively under reduced pressure.

Abstract: A process is described for preparing 3-pentenenitrile, characterized by the following process steps: (a) reacting 1,3-butadiene with hydrogen cyanide over at least one catalyst to obtain a stream 1 which comprises 3-pentenenitrile, 2-methyl-3-butenenitrile, the at least one catalyst and 1,3-butadiene, (b) distilling stream 1 in a column to obtain a high-1,3-butadiene stream 2 as the top product and a low-1,3-butadiene stream 3 as the bottom product which comprises 3-pentenenitrile, the at least one catalyst and 2-methyl-3-butenenitrile, (c) distilling stream 3 in a column to obtain a stream 4 as the top product which comprises 1,3-butadiene, a stream 5 which comprises 3-pentenenitrile and 2-methyl-3-butenenitrile at a side draw of the column, and a stream 6 as the bottom product which comprises the at least one catalyst, (d) distilling stream 5 to obtain a stream 7 as the top product which comprises 2-methyl-3-butenenitrile, and a stream 8 as the bottom product which comprises 3-pentenenitrile.

Abstract: The present invention relates to a process for the manufacture and separation of dinitrile compounds. It relates more particularly to a process for the manufacture and separation of dinitrile compounds from a medium originating from the hydrocyanation of unsaturated mononitriles. The invention consists in feeding the medium comprising the dinitriles to a distillation column and then recovering the purified dinitriles as intermediate fraction, the heavy products being removed as column tail fraction and the light products, including the unsaturated mononitriles, being recovered as top fraction.

Abstract: A process for purifying a nitrile such as acrylonitrile is disclosed. The process comprises (1) contacting a product mixture, which comprises acrylonitrile and hydrogen cyanide, with an acid or a precursor of the acid to produce an acid-treated product; and (2) recovering the nitrile from the acid-treated product. The product mixture can be produced by contacting ammonia with a hydrocarbon such as an olefin under a condition effective to produce a nitrile and hydrogen cyanide.