Process for the recovery of selenium from urethanes containing selenium or compounds thereof

A process for the recovery of selenium or compounds thereof from selenium-containing urethane solutions derived from the selenium catalyzed reaction of an organic compound containing at least one hydroxyl group with carbon monoxide and a nitrogenous organic compound at elevated temperatures and pressures in the presence of a base and/or water, which comprises treating said urethane solution with a mixture of metals and metal oxides at a temperature in the range of from about 25.degree. to 250.degree. C. to retain and remove said selenium or compound thereof from said urethane solution, said metals and metal oxides being selected from metals and oxides of Group IB, IIB, VIB and VIIIB metals of the Periodic Table of Elements, recovering the treated urethane solution, and subjecting the mixture of metal and metal oxide with retained selenium or compounds thereof to treatment with air or oxygen at a temperature of from 250.degree. to 800.degree. C. and pressures of up to 50 atmospheres to convert the selenium to selenium dioxide, and recovering said selenium dioxide from said mixture of metal and metal oxide for reuse in said selenium catalyzed reaction.