Selective oxidative coupling of methane catalysed over hydroxyapatite ion-exchanged with lead

Abstract

Oxidative coupling of methane to ethane and ethene can be effectively catalysed over hydroxyapatite ion-exchanged with lead at reaction temperatures as low at 700 °C, while hydroxyapatite itself catalyses methane oxidation mainly to carbon oxides. The rate of oxygen conversion over the former apatite is almost the same as that with the latter catalyst, suggesting that the oxidation sites on the two apatites are similar. The experimental results suggest that the lead ions on the surface of apatite play an important role in both the activation of methane and stabilization of methyl radicals on the surface.