Enhancement of the catalytic activities in propane oxidation and H–D exchangeability of hydroxyl groups by the incorporation with cobalt into strontium hydroxyapatite

The oxidative dehydrogenation of propane to propylene on strontium and cobalt–strontium hydroxyapatites (SrHAp and Co–SrHAp, respectively) and H–D exchangeability of hydroxyl groups in those catalysts with D2O have been studied. Both the yield of C3H6 and H–D exchangeability were found to be enhanced with increasing the cobalt contents in the catalysts, the latter of which was investigated by solid state 1H MAS MNR at 25 kHz. It is suggested that oxygen species, like lattice oxygen in oxide catalysts, as formed from hydrogen desorption from OH groups in the hydroxyapatites, may contribute to the activation of C3H8. The structure of Co–SrHAp, of which the XRD pattern was identical to that of SrHAp, was also identified with extended X-ray absorption fine structure (XAFS) and solid state 31P MAS NMR.