Process and catalyst for the preparation of aromatic amines by hydrogenation in the gas phase

摘要

Prodn. of aromatic amines of formula (I) comprises gas phase hydrogenation of nitroaromatics of formula (II) with H2 over a stationary catalyst of Pd on a graphite of graphitised coke support with a BET surface area of 0.2-10 m<2>/g. The novel features are that (a) the catalyst contains more than 1.5 to 7 wt.% Pd w.r.t. total catalyst and (b) the H2 supply to the catalyst is 30-6000 equiv./NO2 gp. equiv.: R1, R2 = H, Me, Et or NH2; R3, R4 = H. Me, Et or NO2. Also claimed is the catalyst per se.