2470.     NIKITIN, N. I., AND SHARKOV, V. I.  [Adsorption of Gases by Finely Disintegrated Metals.]  Jour. Russian Phys.-Chem. Soc., vol. 58, 1926, pp. 1095-1100; Chem. Abs., vol. 22, 1928, p. 1074.

        Adsorption of H₂, CO₂ and NH₃ gases was investigated.  The following powders were used:  Cu, Pb, Fe, Co, Ni, Ni-Al₂O₃ mixture and Ag.  Pb and Cu powders were obtained by reducing the basic compounds.  Ag was obtained from the silver gel, which was dried in vacuum.  Virtually no adsorption could be noticed with Pb or Cu powders; this is probably due to recrystillation of metals during the process of reduction.  Ag adsorbed only a small amount of H₂, considerably more of CO₂.  5.512 gm. adsorbed 13.9 cc. of CO₂ (converted to 760 mm. and 0°) at –81°.  Pyrophoric Fe adsorbed 11.5 cc. NH₃ at 97° and 158.6 mm. and 53.7 cc. at –18.2° and 556 mm.  No adsorption occurred at higher temperature.  Co adsorbs 10 times less than Fe.  Ni powder did not adsorb any gases except when mixed with Al₂O₃.  A mixture of 82.4% Ni and 17.6% Al₂O₃ was able to adsorb gases.  4.454 gm. adsorbed at 15°, 760 mm., 190 cc. NH₃; at –18.2°, 760 mm., 281 cc.  After heating and applying vacuum, this mixture was freed from NH₃, gas and used again for the adsorption of CO₂.  At 15° and 760 mm. 15.9 cc. CO₂ gas was adsorbed.  Al₂O₃ without Ni, 4.6338 gm., adsorbed at 15° and 760 mm., 168 cc. gas.  H₂ not adsorbed by Al₂O₃.