Method of accelerating methanol carbonylation

摘要

According to a method for producing acetic acid by carbonylation of methanol characterized in that an acid having an acid dissociation constant (pKa) smaller than the constant of acetic acid is allowed to be present in the reaction system, acetic acid can be produced by the reaction of methanol and carbon monoxide in a reaction liquid in the presence of a solid catalyst containing rhodium and alkyl iodide, to achieve an enhanced reaction rate of carbonylation of methanol in producing acetic acid in the region at a high carbonylation degree (Ca>0.8 mol/mol) for more efficient production of acetic acid.

主权项

1. A method for producing acetic acid by heterogeneous carbonylation of methanol with carbon monoxide in a reaction liquid in the presence of alkyl iodide and a solid catalyst containing rhodium and including hydrolysis of methyl acetate,
wherein the hydrolysis of the methyl acetate is accelerated by an acid having an acid dissociation constant (pKa) smaller than the constant of acetic acid, that acid being co-existent with the solid catalyst in the reaction system; wherein the carbonylation of methanol is performed in a region where liquid reaction product has a carbonylation degree Ca not lower than 0.7 mol/mol; and wherein the rhodium is supported on a carrier comprising a sulfonated copolymer of 4-vinylpyridine, styrene, and divinylbenzene.