METHOD FOR RECOVERY AND RECYCLE OF RUTHENIUM HOMOGENEOUS CATALYSTS

摘要

Disclosed is a process for the extractive recovery of a homogeneous ruthenium catalyst from the reaction product of the hydrogenation of glycolic acid, glycolate esters, and/or glycolic acid oligomers with an extractant comprising a hydrophobic solvent and an optional hydrophilic solvent. The ruthenium catalyst, which can include 1,1,1-tris(diaryl- or dialkylphosphinomethyl)alkane ligands, can be recovered from the hydrophobic extract phase by back extraction with a hydrophilic solvent and recycled to a process for the preparation of ethylene glycol by the hydrogenation of glycolic acid and glycolic acid derivatives.