METHOD FOR THE HYDROGENATION OF AROMATIC NITRO COMPOUNDS

• Main Authors: GERDINAND, Martina, PENNEMANN, Bernd, WILLIAMS, Marc, SANDBRINK, Lennart, QUELLA, Hans-Jürgen, ZIRNGIEBL, Eberhard, ULLRICH, Daniel
• Format: Patent
• Language: English; French; German
• Published: 06.07.2022
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; METALLURGY; ORGANIC CHEMISTRY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; THEIR RELEVANT APPARATUS; TRANSPORTING

The present invention relates to a process for the preparation of an aromatic amine by hydrogenation of an aromatic nitro compound, comprising the following steps: (I) providing a copper tetramine salt-based impregnation catalyst, in particular an impregnation catalyst obtainable by the incipient wetness method, comprising a metal or metal oxide on a support as a hydrogenation catalyst. At least metallic or oxidic copper (in particular CuO) is present and the mole fraction of Cu based on all metals present is in the range of 075 to 1, and wherein the support comprises shaped silicon-dioxide shaped bodies or silicon-carbide shaped bodies; (II) optionally, activating the hydrogenation catalyst by treating with hydrogen in the absence of the aromatic nitro compound; and (III) reacting the aromatic nitro compound with hydrogen in the presence of the, optionally activated, hydrogenation catalyst to obtain the aromatic amine.