METHOD FOR REDUCING EDA IN ACETIC ANHYDRIDE PRODUCTION

摘要

In a liquid phase carbonylation process for the production of acetic anhydride by reacting a feed stream which includes methyl acetate, methanol and carbon monoxide using a Group VIII metal-containing catalyst, and preferably a rhodium containign material, a liquid reaction product is continuoulsy withdrawn from the carbonylation zone and fed to an evaporaton/separation zone for separating volatile constituents of the reaction from the non-volatile constituents whihc, includes a portion of the Group VIII metal catalyst from the carbonylation reactor. The Group VIII metal catalyst is contacted with a gas stream which includes hydrogen for a period of from about 0.001 seconds to about 200 seconds as it is being returned to the carbonylation zone.