Rhodium-catalyzed carbonylation using non-acetate lithium, sodium and potassium inorganic salts as promoters to produce carboxylic acids

摘要

The present invention relates to an improved process for producing an organic carboxylic acid having (n+1) carbon atoms by reacting an alcohol having n carbon atoms with carbon monoxide in the presence of a rhodium catalyst system. More particularly, the present invention relates to carbonylation of alcohol such as methanol catalyzed by a rhodium system to produce acetic acid. The characteristic of the present invention is the addition of a catalyst stabilizer in the reaction medium to avoid or to alleviate the precipitation of the catalyst in the liquid phase. The catalyst as used herein is a an inorganic salt of alkaline metal having the following formula (A):X=Li+, Na+, K+;M=CO3-2, HCO3-, PO4-3, HPO4-2, H2PO4-, SO4-2, HSO4-, C2O4-2, HC2O4-, B(C6Y5)4-1;Y=H, F or CF3.