RHODIUM RECOVERY FROM HYDROFORMYLATION STILL HEEL WITH TRIARYL PHOSPHITE LIGAND

摘要

Title Rhodium Recovery from Hydroformylation Still Heel with Triaryl Phosphite Ligand A process for recovering rhodium present in a still heel from the hydroformylation of an unsaturated hydrocarbon wherein rhodium and a triaryl phosphite ligand were used characterized by (a) pretreating the still heel with a compatible organic solvent or a mixture thereof, at least 5 ml of water per 100 g of still heel, oxygen gas or a precursor thereof and sufficient base to produce a pH of 2 to 7 in the reaction mixture after rhodium precipitation; (b) heating to a temperature of from 0.degree. to 80.degree.C to oxidize the triaryl phosphite ligand to the corresponding phosphate compound; and (c) heating the mixture from (b) for from about 15 minutes to about 120 minutes at about 115.degree.C to about 175.degree.C to precipitate zero valent rhodium; and optionally purifying the precipitated rhodium from (c) by converting from zero valent form to Rh2O3.