PARTIAL OXIDATION OF METHANE CATALYZED BY YBA2CU3OX IN A SOLID-STATE ELECTROCHEMICAL REACTOR

The catalytic oxidation of methane was studied between 840 and 1110 K on a YBa2Cu3Ox mixed-conducting electrode deposited on an yttria stabilized zirconia solid electrolyte. The lattice oxygen supplied electrochemically to the catalyst surface actively participated in the oxidation reaction, with CO as the major product, and CO2, CH3OH and HCHO as the minor products. The reaction rate was found to be of first order with respect to methane. The rate constant depended strongly on the electrochemically imposed bias. Under DC bias condition, the reaction rate was enhanced by as much as two orders of magnitude over that observed under open-circuit conditions. An Eley-Rideal mechanism for the interaction of CH4 with surface oxygen is proposed as the rate-determining step.