Patent ID: 7528277

Claim:
A method to obtain a carboxylic acid ester from an aqueous solution of the carboxylic acid ammonium salt comprising (a) providing (i) an aqueous solution comprising a carboxylic acid ammonium salt; said carboxylic acid ammonium salt having the formula: R 1 —C(O)O − NH 4 + or NH 4 +− O(O)C—R 1 —C(O)O − NH 4 + wherein R 1 =C1 to C6 hydrocarbyl group independently selected from the group consisting of alkyl, cycloalkyl, and aryl; optionally substituted with at least one hydroxyl group; and (ii) a heated alcohol vapor feed stream comprising an alcohol having the formula: R 2 —OH wherein R 2 is a C1 to C2 alkyl group; and (iii) a reaction vessel (b) contacting said aqueous solution comprising carboxylic acid ammonium salt with said heated alcohol vapor feed stream in said reaction vessel whereby the heated alcohol vapor stream acts both as an esterifying agent and a stripping gas to produce a first vapor product stream comprising a carboxylic acid ester; (c) separating within the reaction vessel the carboxylic acid ester from the aqueous solution; and (d) recovering the carboxylic acid ester from said first vapor product stream using a condenser or a distillation column.