| abstract |
A process for preparing a carboxylic acid having (n+1) carbon atoms (e.g. acetic acid) from an alcohol having n carbon atoms (e.g. methanol) by liquid phase, rhodium catalysed carbonylation is provided. The process is characterised by using a catalyst stabiliser selected from certain classes of imidazolium iodides, alkyl substituted pyridinium iodides and hydroxypyridinium iodides. Most preferred are those derived from the amines 2-ethyl-4-methylimidazole, 4-methylimidazole, 4-ethylpyridine, 4-t-butylpyridine and 3,4-lutidine by quaternisation with a methyl group. |