Patent ID: 9029595
Filing Date: 2015-05-12
Classification: C07C

Abstract:
1. A process for the preparation of an isocyanate, comprising: a) phosgenating of a primary amine to obtain a crude process product comprising the corresponding isocyanate, b) working up of the crude process product obtained under a), wherein the working up comprises at least one distillation step in which monomeric isocyanate, as the distillate, and a distillation residue comprising monomeric isocyanate are obtained, c) working up of the distillation residue obtained under b) by spraying the distillation residue and a carrier gas into a reactor, the distillation residue and the carrier gas flowing vertically downwards, so that the monomeric isocyanate vaporizes partly to completely and a dried residue which has been largely to completely freed from monomeric isocyanate and a stream comprising monomeric isocyanate are obtained.