Kinetic Study of Carbonylation of Methyl Acetate to Acetic Anhydride Catalyzed by Rhodium Complex with a Ligand of Copolymer of Vinyl-acetic Ester and Acrylonitrile

摘要

The copolymer of vinyl acetic ester and acrylonitrile is used to react with [Rh（CO）₂Cl]₂to form a complex which can be used in the carbonylation of methyl acetate to acetic anhydride. Many factors affecting the reaction rate, catalytic activity and selectivity have been investigated. The reaction rate depends on rhodium complex and methyl iodide, and is differant from that of homogenous small molecular rhodium complex catalyst. It is revealed thatthe reaction rate is zero order in CO, first order in Rh and LiOAc, but the order in CH₃I is complicated. The causes of these phenomena are discussed based on the mechanism of carbonylation of methyl acetate.