Oxidative coupling of methane using carbon dioxide in an electric field over La–ZrO2 catalyst at low external temperature

Abstract Oxidative coupling of methane using carbon dioxide (CO 2 –OCM) as an oxidant was conducted over several La- and Zr-based catalysts in an electric field at low external temperature of 423 K. Higher catalytic activity was obtained than in a conventional catalytic reaction over 10 mol% lanthanum-doped zirconia (La–ZrO 2 ) in the electric field. Although the catalytic activity for the CO 2 –OCM was low over the La–ZrO 2 at 1173 K without the application of the electric field, the electric field promoted catalytic activity even at 423 K external temperature. We optimized the amount of doping-La in the La–ZrO 2 system, and characterized the effect of doping-La with XRD measurement. From these examinations, 5 mol% La–ZrO 2 catalyst showed the highest activity. High catalytic activity was provided by the synergistic effect of the La-cation, tetragonal-ZrO 2 , and the electric field.