2152.     LUYTEN, L.  [Kinetics of the Methane Synthesis on Nickel.]  Natuurw. Tijdschr., vol. 23, 1941, pp. 25-26; Chem. Zentralb., 1942, I, p. 25; Chem. Abs., vol. 37, 1943, p. 3662.

        Experiments on the poisoning effect of CO on the active Ni used as catalysts in the synthesis of CH₄ from CO and H₂, including those in which D was used, show that the reaction velocity, S_CH4=k[H₂]1/2/[CO]1/2 and S_CD4=k¹[D₂]1/2/[CO]1/2, where k¹/k=1.15 and 1.025 at 250° and 300°, respectively.  The higher the CO content of the gas mixture and the smaller the activity of the catalyst, the greater the difference between the reaction velocities of the 2 isotopes become, since in both cases the number of active centers remaining for adsorption of H or D is smaller and the difference between the z and the smaller the activity of the catalyst, the greater the difference between the reaction velocities of the 2 isotopes become, since in both cases the number of active centers remaining for adsorption of H or D is smaller and the difference between the zero-point energies causes a relatively greater difference between the two isotopes.  Apparent activation energies are:  E_CH4=27,100 cal.; E_CD4=24,900 cal. E_apparent=E_actual-3λH₂-λ_CO, where λ is the heat of adsorption.