2468.     NIKITIN, N. I.  [Absorption of Hydrogen and Carbon Dioxide by Pyrophoric Iron, Nickel, and Cobalt.]  Jour. Russian Phys.-Chem. Soc., vol. 58, 1926, pp. 1081-1094; Chem. Abs., vol. 22, 1928, p. 8.

        Finely divided Fe, obtained by the action of H2 on the carbonate at 515-525, adsorbed H2 at 185 according to the equation a=βp1/n.  No adsorption was observed at 80 and +16, while at 330 the gas diffuses through Fe.  The adsorption isotherm of Ni at 19 is parallel to the axis of pressures showing compound formation.  No combination occurs at 185, since the corresponding isotherm begins at the origin.  The 336 curve crosses that for 19; its lower portion represents the dissociation of the Ni and H2 compound.  The above equation holds for Fe and CO2 at 18 (1/n=0.207).  Readsorption, after evacuating the system at 500, was much smaller although similarly represented by a straight line; a slow reaction occurs at 500.  Ni adsorbs little CO2 at 14 and 335; the gas is only partly recovered by evacuation.  Erratic results were obtained with Co prepared at 340.  A sample reduced at 525-550 exhibited a continuous adsorption isotherm for CO2 at 14.  Co lies between Ni and Fe as an adsorbent of CO2.