Partial oxidation of methane over Ni/Mg/Al/La mixed oxides prepared from layered double hydrotalcites

A series of Ni/Mg/Al/La mixed oxides prepared by thermal decomposition of layered double hydrotalcites (HT) were characterized by XRD, ICP, EXAFS, TGA, TPR-H2, SEM, and N2 adsorption/desorption technique. The results revealed the formation of periclase-type catalysts with mesoporous structure, and the addition of La3+ lowered the phase crystallization with the formation of small oxide particles. Such catalysts had both high activities and stabilities toward partial oxidation of methane (POM). The catalyst containing 6.5 mol.% La3+ showed the highest performance at 1053 K with CH4 conversion of 99%, CO selectivity of 93% and H2 selectivity of 96%, which could be attributed to the presence of highly dispersed nickel and then the resistance to coke formation due to the promotion effect of lanthanum.