Patent ID: 8779214

Claim:
A process for recovering a homogeneous catalyst, comprising (A) contacting an aqueous mixture comprising glycolic acid, glycolate esters, methyl glycolate, oligomers of glycolic acid, or mixtures thereof, with hydrogen in the presence of a catalyst composition comprising ruthenium and tris-1,1,1-(diphenylphosphinomethyl)ethane to form a glycolic acid hydrogenation product comprising about 50 to about 90 weight percent, based on the total weight of said glycolic acid hydrogenation product, ethylene glycol, about 0.5 to about 25 weight percent water, and about 0.5 to about 30 weight percent of one or more reaction by-products selected from glycolic acid, oligomers of glycolic acid, and glycolate esters of ethylene glycol, and said catalyst composition; (B) extracting said glycolic acid hydrogenation product with a first extractant, comprising about 60 to 100 weight percent, based on the total weight of said first extractant, 2-ethylhexanol and about 0 to about 40 weight percent of a hydrocarbon having 5 to 20 carbon atoms to form a first raffinate phase comprising a major amount of said ethylene glycol contained in said glycolic acid hydrogenation product and a first extract phase comprising a major amount of said catalyst composition contained in said glycolic acid hydrogenation product; (C) separating said first raffinate and extract phases; (D) extracting said first extract phase from step (C) with a second extractant comprising water, ethylene glycol, glycolate esters of ethylene glycol, glycolic acid, glycolic acid oligomers, or mixtures thereof to form a second extract phase comprising a major amount of said catalyst composition contained in said first extract phase from step (C) and a second raffinate phase comprising a minor amount of said catalyst composition contained in said first extract phase; and (E) combining said second extract phase with said aqueous mixture of glycolic acid of step (A).