Acetic acid free from formic acid - prepd. by liquid phase acetaldehyde oxidn. with catalyst contg. salts of cobalt, manganese and nickel

摘要

Practically HCOOH-free AcOH is prepd. by liquid-phase oxidn. of AcOH with O2 -contg. gases in the presence of catalysts contg. mixts. of Co-, Mn- and Ni salts. HCOOH concn. in crude AcOH obtd. can be reduced to 100 ppm. Distn. columns used of VA-steel instead of expensive special materials. Losses of AcOH are reduced. By-prod. quantity, e.g. of MeOH, AcOMe, CO2, CH4 and H2O, is not increased, and AcOH yield is not reduced. Catalyst-contg. residue remaining after distilling off AcOH formed can be re-used in reaction. Catalyst activity is not impaired by presence of other salts, e.g. of Fe, Cr, Mo, Ti.