Process for making nitriles

• Main Authors: MOERBE LARRY E, CHAO TSENG H
• Format: Patent
• Language: English
• Published: 27.10.2015
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION ORPROCESSING OF GOODS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; METALLURGY; ORGANIC CHEMISTRY; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINSTCLIMATE CHANGE

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.