Patent ID: 6482976
Filing Date: 2002-11-19
Classification: C07C,Y02P

Abstract:
A process for conducting an equilibrium-limited reaction of at least one carboxylic acid and at least one alcohol to produce at least one ester product comprising:a. reacting at least one carboxylic acid-containing feedstock with at least one alcohol-containing feedstock in the presence of an esterification catalyst selected from the group consisting of a sulfuric acid, a sulfonic acid or an acidic exchange resin in a single reaction zone that is a stirred or agitated vessel, wherein the reaction zone contains about 1 weight percent water or less, maintained under reaction conditions sufficient to produce at least one ester product, said reaction conditions comprising a temperature and pressure sufficient to crack heavies formed in or introduced into said single reaction zone and to vaporize at least a portion of said at least one ester product upon production thereof; b. withdrawing vapor from said single reaction zone, and introducing said withdrawn vapor into the lower portion of an acid separation column, said acid separation column comprising a rectification zone above the point where said withdrawn vapor is introduced into said acid separation column and a stripping zone below the point where said withdrawn vapor is introduced into said acid separation column, to provide in said rectification zone an overhead fraction comprising said at least one ester product and in said stripping zone a bottoms fraction comprising water and said at least one carboxylic acid; c. withdrawing from the acid separation column the bottoms fraction and supplying at least a portion of the withdrawn bottoms fraction to said single reaction zone; and d. withdrawing from the acid separation column the overhead fraction and recovering said at least one ester product from the overhead fraction; wherein said ester product is represented by the formula Râ€²C(O)ORâ€²â€³, said carboxylic acid is represented by the formula Râ€²C(O)OH, and said alcohol is represented by the formula Râ€²â€³OH wherein Râ€² is a hydrocarbyl-containing group of 1 to about 8 carbon atoms and Râ€²â€³ is a hydrocarbyl-containing group of 1 to about 12 carbon atoms.