Partial Oxidation of Methane to Carbon Oxides and Hydrogen on Hydroxyapatite:  Enhanced Selectivity to Carbon Monoxide with Tetrachloromethane

Abstract

On stoichiometric hydroxyapatite [Ca 10 (PO 4 ) 6 (OH) 2, Ca/P = 1.67] the partial oxidation of methane at 973 K yields carbon oxides as the principal products, with a selectivity to CO of approximately 40%, while on calcium oxide, phosphate, and sulfate, C 2 hydrocarbons predominate. On introduction of tetrachloromethane (TCM) into the feedstream the selectivity to CO is increased to 71% on hydroxyapatite while, in contrast, with the remaining calcium compounds the conversion of methane and/or the selectivities to C 2 compounds, particularly to C 2 H 4, are enhanced.