2143.     LOTTERI, A.  [Catalytic Incomplete Oxidation of Methane With Free Oxygen.]  Kraftstoff, vol. 17, 1941, pp. 137-140; Brennstoff-Chem., vol. 22, 1941, p. 211; Chim. e ind. (Milan), vol. 23, 1941, pp. 126-129, 175; British Chem. Abs., 1942, B, I, p. 19; Chem. Abs., vol. 35, 1941, p. 5284.

        Equilibrium constant at different temperature of the synthesis gas reactions CH₄+1/2O₂=CO+2H₂+8.8 cal. was calculated from the published equilibrium constants of the reactions (a) CH₄=C+2H₂, (b) C+CO₂=2CO, (c) CH₄+H₂O=CO+3H₂, and (d) CH₄+2O₂=CO₂+2H₂O.  In mixtures of CH₄ and O₂ above 650°, incomplete combustion of CH₄ prevails over complete combustion (d) more and more with rising temperature.  Calculation for a mixture comprising O₂, 33; CH₄, 66; and N₂, 1% shows that at 750°-850° the equilibrium has shifted almost entirely towards the formation of synthesis gas.  (CO:H₂=1:2).  When a 2:1 mixture of 92.1% CH₄ and 97-98% O₂ was passed at different space velocities at 890°-960° through a quartz tube filled with a catalyst (ceramic carrier saturated with aqueous Ni nitrate containing activators, subsequently calcined and reduced with H₂), the experimental and calculated data were in good agreement.  At 900°, only 1-2% of CH₄ remained at all space velocities employed, and at 920°-960° the residual CH₄ was <1%.  Since small quantities of heavy hydrocarbons contained in the original gas mixture were completely converted at low temperature, they appear to be more readily oxidizable than CH₄.  Tests made in alloy steel tubes yielded similar results; this fact together with the good performance of the catalyst, indicate that technical application of the process is possible but especially since the reaction velocity is > in the cases of conversion of CH₄ with CO₂ (b) or with H₂O (c).