N,N-di:methyl:aniline prodn. - by gas-phase reaction of aniline and methanol or di:methyl ether, on mixt. of aluminium oxide and phosphorus pent:oxide as catalyst

摘要

N,N-dimethylaniline (I) is produced by reaction of aniline and methanol or dimethyl ether, in the gas phase, in the presence of a catalyst comprising mixt. of 70-99 wt.% aluminium oxide (II) and 1-30 wt.% phosphorus pentoxide (III). Pref. the catalyst is produced by mixing finely-divided (II) with H3PO4 to form a paste which is pelleted, tabletted, etc., dried and heated to 100-500 deg.C to remove chemically-bound water; the catalyst is pref. used in a solid-bed contact process. USE/ADVANTAGE - (I) is an important raw material for the mfr. of dyestuffs, etc. The combination of (II) and (III) has higher activity than prior-art catalysts; it has esp. low loss of activity w.r.t. conversion and selectivity, and can be easily regenerated by addn. of fresh (III).