Facile Formation of the Partial Oxidation and Oxidative-Coupling Products from the Oxidation of Methane on Barium Hydroxyapatites with Tetrachloromethane

Abstract

The oxidation of methane on PO 4 -deficient barium hydroxyapatite (BaHAp) has been investigated in the presence and absence of tetrachloromethane (TCM). In the absence of TCM, the principal product was CO 2 with less than 20% selectivity to partial oxidation and oxidativecoupling products. On introduction of a small partial pressure of TCM to the feedstream and with higher times-on-stream, the formation of CO 2 was virtually eliminated while CO and the C 2 hydrocarbon became the dominant products. The observations with TCM can be attributed to the chlorination of the catalyst and, in particular, the formation of the corresponding chlorapatite.

Partial oxidation of n-pentane over vanadium phosphorus oxide supported on hydroxyapatites

“…Three oxygen atoms from each PO 4 tetrahedron are shared by one column and the fourth oxygen atom is attached to the neighbouring column. The lattice of HAp is structured to allow substitution of the calcium ions with other cations by ion exchange and ion adsorption or a combination of these methods to improve its catalytic performance 15,[17][18][19] . Co-HAp offers high stability and the OH group within the phosphate framework leads to the formation of active oxygen species which are essential for ODH reactions 14,20,21 .…”