3746.     WRIGHT, M. M., AND TAYLOR, H. S.  Interaction of Methane and Methane-d4 on Nickel and the State of the Catalyst Surface.  Canadian Jour. Research, vol. 27, 1949, B, pp. 303-317; Chem. Abs., vol. 43, 1949, p. 7802.

        Mass spectrometer studies of the exchange reaction and the reaction of H2 with catalyst surface residues support the concept of dissociative adsorption.  Evidence of fragments, such as CX3, CX2, CX, C (X=H or D), was obtained.  The first order disappearance of CD4 has an activation energy of 20.9 kcal. at 100-255.  Temperature increases the concentration of the more hydrogenated fragments (larger i for CDi and CHi), and equilibrium between the fragments depends on the heats of adsorption of the fragments and H on the surface and, therefore, on the nature of the catalyst and on the strength of CH bonds formed.  Experimental details, tables, and graphs.