METHOD OF CARBOXYLIC ACIDS BY CARBONYLATION IN THE PRESENCE OF RHODIUM Russian patent published in 2000 - IPC

FIELD: chemical industry. SUBSTANCE: described is method of preparing carboxelic acids by carbonylation of saturated C₁-C₁₀ mono-or diatomic alcohol or derivative thereof selected from group consisting of halogen derivative, ether and/or ester with carbon monoxide in the presence of rhodium-based catalyst. Liquid phase reaction is carried out in first zone in the presence of rhodium catalyst, and the resulting reaction mixture is partially evaporated in second stage. Carboxylic acid-containing acid fraction resulting from evaporation, is then purified, and the remaining catalyst-containing fraction after evaporation is recycled into first zone. Method comprises contacting liquid fraction remaining after evaporation with carbon monoxide so that carbon monoxide is not recycled into second zone. EFFECT: more efficient preparation method. 7 cl, 3 dwg