3399.     THOREN, F.  [Activity and Temperature Relationships for Nickel Catalysts.  I.]  Ztschr. anorg. Chem., vol. 163, 1927, pp. 367-395; Chem. Abs., vol. 21, 1927, p. 3804.

        Activities of Ni catalysts prepared in various ways were measured by a static method.  The reactions used were:  C₂H₄+H₂→C₂H₆; C₆H₆+3H₂→C₆H₁₂; O₂+2H₂→2H₂O.  The activity of the catalysts increased stepwise with increase in temperature.  The mean values for the temperatures at which marked increase in activity was evidenced were 9.7°, 40.1°, 60.2°, 80.7°, 100.3°, 119.4°, 134.7°, 170.0°.  The actual % increase in activity at the various activation temperatures was not reproducible.  The activation temperatures were almost the same for all reactions and for different Ni catalysts.  The activation of the H₂ is considered to be the cause of the phenomenon.