4014.  [Regenerating Used Hydrogenation Catalysts.] German Patent Appl. B 201,899, PA 292,062, Mar. 23, 1943. FIAT Reel B 196, frames 743-745; PB 83,253.

Method is given for regenerating used Co hydrogenation catalysts by dissolving them in HNO₃ after removal of the greater part of the organic substances by treating while warm, with solvents, gases or vapors. Before the catalysts are dissolved in acid at temperatures < about 700° they are oxidized with air by this means a considerable saving of acid is reported.