182.    BEL’KEVICH, P. I.  [Sorption of Hydrogen by Metals of the Platinum Group.  I.  Character of the Sorption Isotherms of the Iridium-Hydrogen, Rhodium-Hydrogen, Osmium-Hydrogen and Ruthenium-Hydrogen Systems.]  Jour. Gen. Chem. (U.S.S.R.), vol. 9, 1939, pp. 944-954; Chem. Abs., vol. 33, 1939, p. 8468.

                  Sorption isotherms for 20° and 50° for the Ir-H₂, Rh-H₂, and Os-H₂ systems are analogous to that of the Pt-H₂ system.  The metals were used in the finely dispersed form (Ir, Os, Rh, and Ru blacks), prepared by the reduction of their chloride salts with hydrazine-HCl in weakly alkaline solution.  By strict control of thermal conditions of treatment of blacks (temperature of sorption 20° and 50° and that of desorption for Ir 120° and for Rh and Os 150°), reproducible isotherms can be obtained.  An increase in temperature of sorption and desorption causes decrease in the sorptive power of the blacks.  Data are tabulated and plotted.  44 references covering the period from 1866-1926.