A process is presented for treating and detoxifying mixed wastes, especially those containing volatile chemically oxidizable organics, nonvolatile inorganics and radioactive pollutants. The process combines an efficient extraction system, a filtration step, and evaporation system to concentrate the pollutants originally present in the mixed waste and a catalytic oxidation reaction to convert the volatilized organic and inorganic pollutants. A condensate product is obtained that is recycled internally to provide a closed system that discharges only inert gases and treated solid products.