US 10,927,066 B2 · Process for hydrogenating a mixture in the presence of a colorless amine

Abstract

The present invention relates to a process for hydrogenating a mixture (G1) in the presence of a catalyst, where the mixture (G1) comprises at least one colorless amine and at least one color-imparting component. As a result of the hydrogenation step, the at least one color-imparting component is firstly partially, preferably fully, hydrogenated, while the colorless amine, in particular aniline, is not hydrogenated or hydrogenated to only a very small extent. The color-imparting components which cause the discoloration of the amine which is itself in principle colorless are thus removed by hydrogenation, as a result of which purification of the colorless amine or the mixture (G1) is achieved.

Claims16

Dependent claims

A process for hydrogenating a mixture (G) which comprises at least one colorless amine and at least one color-imparting component, the process comprising:

hydrogenating the mixture (G) in the presence of a catalyst to obtain a mixture (G2) in which the at least one color-imparting component is at least partially or completely hydrogenated, and
converting the at least one colorless amine comprised in the mixture (G2) into a diphenylmethane derivative, and optionally converting the diphenylmethane derivative into an aromatic isocyanate, optionally by phosgenation;
wherein the at least one color-imparting component is selected from the group consisting of a cycloaliphatic carbonyl compound, a cycloaliphatic amine, a cycloaliphatic imine and a C6-ring aromatic.

Dependencies are inferred from the claim text.

Facts

Application

16/333,142Filed 31 Aug 2017

Priority

EP 1618885114 Sep 2016

Published

US 2019/0210955 A111 Jul 2019

Granted

23 Feb 2021

Term ends

Not estimatedThe source records don’t support an estimate.

Classification6 codes

C07C 209/72
By reduction of unsaturated amines: by reduction of six-membered aromatic rings
C07C 209/82
Preparation of compounds containing amino groups bound to a carbon skeleton: purification; Separation; Stabilisation; Use of additives
C07C 209/84
Purification; Separation; Stabilisation; Use of additives: purification
C07C 209/90
Purification; Separation; Stabilisation; Use of additives: stabilisation; Use of additives

Process for hydrogenating a mixture in the presence of a colorless amine

Life of this patent

Process for hydrogenating a mixture in the presence of a colorless amine

Life of this patent

Abstract

Claims16