Aminopolycarboxylates as rate promoters for the glacial acetic acid process

A method for reducing water in an acetic acid production process comprising:

• a) combining methanol, methyl acetate or any mixture of the two, and carbon monoxide in the presence of a reaction mixture comprising iodide under carbonylation conditions sufficient to form acetic acid at a first rate, wherein the reaction mixture comprises:
• i) a carbonylation catalyst, selected from the group consisting of rhodium catalysts, iridium catalysts, palladium catalysts, and cobalt catalysts;
• and
• ii) a first amount of water, where the water is present in the range of from 0.1 wt % to 10 wt %, based on the weight of the reaction mixture;
• and
• b) combining one or more promoters to the reaction mixture at an iodide to promoter molar ratio of greater than 2, wherein the one or more promoters are selected from the group consisting of Group I and Group II aminopolycarboxylate salts and mixtures thereof;
• and
• c) reducing the wt % of water in the reaction mixture to a second amount of water while maintaining a second rate of acetic acid production that is the same as or greater than the first rate of acetic acid production.