Invista North America S.a.r.l.

Invista Technologies S.a.r.l.

Larry E Moerbe

Tseng H Chao

William J Tenn, Iii

Thomas E Vos

Bruce Edwin Murphree

Sudhir Aki

James E McIntosh

Wyatte E Allen

Mark Anstrom

Charles Nelson Campbell, Ii

Mark D Rogers

Michael W Wensing

William J Iii Tenn

Charles Nelson Ii Campbell

Wyatt E Allen

Mark A Anstrom

An improved multi-reaction zone process provides improved nitrile product quality and yield. In a first reaction zone, 1,3-butadiene is reacted with hydrogen cyanide in the presence of a catalyst to produce pentenenitriles comprising 3-pentenenitrile and 2-methyl-3-butenenitrile. In a second reaction zone, 2-methyl-3-butenenitrile, recovered from the first reaction zone, is isomerized to 3-pentenenitrile. In a third reaction zone, 3-pentenenitrile recovered from the first and second reaction zones is reacted with hydrogen cyanide in the presence of a catalyst and a Lewis acid to produce adiponitrile. Unwanted production and build-up of dinitriles, including methylglutaronitrile, in the first reaction zone for the hydrocyanation of 1,3-butadiene is prevented by limiting the flow of Lewis acid into the first reaction zone.

Process for making nitriles

Adiponitrile is made by reacting 3-pentenenitrile with hydrogen cyanide. The 3-pentenenitrile is made by reacting 1,3-butadiene with hydrogen cyanide. The catalyst for the reaction of 1,3-butadiene with hydrogen cyanide to make 3-pentenenitrile is recycled. At least a portion of the recycled catalyst is purified by an extraction process, which separates catalyst degradation products and reaction byproducts, such as mononitriles having 9 carbon atoms, from the catalyst.

Adiponitrile is made by reacting 3-pentenenitrile with hydrogen cyanide. The 3-pentenenitrile is made by reacting 1,3-butadiene with hydrogen cyanide and by isomerizing 2-methyl-3-butenenitrile. Phenolic compounds, such as phenol and cresols, are present as a catalyst impurity or as a catalyst degradation product. Phenolic compounds are removed during the nitrile manufacturing process.

Adiponitrile is made by reacting 3-pentenenitrile with hydrogen cyanide. The 3-pentenenitrile is made by reacting 1,3-butadiene with hydrogen cyanide. The 1,3-butadiene feed includes a small amount of tertiary-butylcatechol. The catalyst for the reaction of 1,3-butadiene with hydrogen cyanide to make 3-pentenenitrile is recycled. At least a portion of the recycled catalyst is purified by an extraction process.

Adiponitrile is made by reacting 3-pentenenitrile with hydrogen cyanide. The 3-pentenenitrile is made by reacting 1,3-butadiene with hydrogen cyanide and by isomerizing 2-methyl-3-butenenitrile. Both reactions take place in the presence of a catalyst comprising zero valent nickel and a phosphorus-containing ligand. The ligand is partially degraded by hydrolysis or oxidation. Phosphorus-containing ligand degradation products are removed during the production of 3-pentenenitrile and adiponitrile.

Adiponitrile is made by reacting 3-pentenenitrile with hydrogen cyanide. The 3-pentenenitrile is made by reacting 1,3-butadiene with hydrogen cyanide. The catalyst for the reaction of 1,3-butadiene with hydrogen cyanide to make 3-pentenenitrile is recycled. At least a portion of the recycled catalyst is purified by an extraction process, which separates catalyst degradation products and reaction byproduct from the catalyst.

An improved multi-reaction zone process provides for improved nitrile product quality and yield. In a first reaction zone, 1,3-butadiene is reacted with hydrogen cyanide in the presence of a catalyst to produce pentenenitriles comprising 3-pentenenitrile and 2-methyl-3-butenenitrile. In a second reaction zone, 2-methyl-3-butenenitrile, recovered from the first reaction zone, is isomerized to 3-pentenenitrile. In an optional third reaction zone, 3-pentenenitrile recovered from the first and second reaction zones is reacted with hydrogen cyanide in the presence of a catalyst and a Lewis acid to produce adiponitrile. A portion of the first catalyst is purified and recycled. Zero valent nickel is added to the purified first catalyst before it is recycled.

Adiponitrile is made by reacting 3-pentenenitrile with hydrogen cyanide. The 3-pentenenitrile is made by reacting 1,3-butadiene with hydrogen cyanide and by isomerizing 2-methyl-3-butenenitrile. The reaction of 1,3-butadiene with hydrogen cyanide to produce 3-pentenenitrile also produces small amounts of dinitrile compounds, including adiponitrile (ADN) and methylglutaronitrile (MGN). Methylglutaronitrile is removed to provide an adiponitrile-enriched stream, which is used in a catalyst purification step.

The present invention relates to a process for hydrocyanating 3-pentenenitrile. The process can include feeding 3-pentenenitrile and HCN to a hydrocyanation reaction zone that includes a Lewis acid promoter, nickel, and a phosphorus-containing ligand. In various embodiments, the process can also include controlling water concentration within the hydrocyanation reaction zone sufficient to maintain a high activity of the ligand catalyst complex while recycling at least a portion of the ligand catalyst complex.

A hydrocyanation reaction is used to react 1,3-butadiene with hydrogen cyanide in the presence of a catalyst to produce pentenenitriles, as well as reaction byproducts, such as methylglutaronitrile (MGN). The effluent from the hydrocyanation reaction is distilled in a particular manner to produce a pentenenitrile-enriched stream, a catalyst-enriched stream and a stream enriched in methylglutaronitrile (MGN). At least a portion of the catalyst enriched stream may be recycled to the hydrocyanation reaction. 3-pentenenitrile may be recovered and, optionally, further reacted with HCN to make adiponitrile (ADN).

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Orange, TX, United States of America

Larry E Moerbe