Patent ID: 8829234
Filing Date: 2014-09-09
Classification: C07C,Y02P

Abstract:
1. A process for the preparation of glycolic acid, comprising (A) feeding carbon monoxide, aqueous formaldehyde, and a carboxylic acid comprising 3-6 carbon atoms to a hydrocarboxylation reaction zone comprising a solid acid catalyst to produce an effluent comprising esters of glycolic and carboxylic acids; (B) hydrolyzing said effluent to produce a hydrolyzed mixture comprising glycolic acid and said carboxylic acid; (C) recovering said carboxylic acid from said hydrolyzed mixture by extracting said hydrolyzed mixture with a hydrophobic solvent selected from at least one of the group consisting of esters having from 4 to 20 carbon atoms, ethers having from 4 to 20 carbon atoms, ketones having from 4 to 20 carbon atoms, and hydrocarbons having from 6 to 20 carbon atoms to form an aqueous raffinate phase comprising a major amount of said glycolic acid contained in said hydrolyzed mixture and an organic extract phase comprising a major amount of said carboxylic acid contained in said hydrolyzed mixture; and (D) separating said aqueous raffinate phase and said organic extract phase.