A Solid Oxide Fuel Cell Running on H[sub 2]S∕CH[sub 4] Fuel Mixtures

Abstract

Solid oxide fuel cells (SOFCs) that were capable of running on sour natural gas were fabricated and tested. The electrolyte of the SOFCs was yttria-stabilized zirconia (YSZ), the anode material was a strontium-doped lanthanum vanadate with a nominal composition of La 0 . 7 Sr 0 . 3 VO 3 (LSV), and the cathode was a porous composite of La 0 . 8 5 Sr 0 . 1 5 MnO 3 (LSM) and YSZ. The observed peak power density at 950°C was 280 mW/cm 2 when 5% H 2 S/95% CH 4 gas mixture was used as the fuel and ambient air as the oxidant. Analysis of the effluent gas from the SOFC indicated that, apart from being oxidized electrochemically to sulfur and SO 2 , a significant portion of the H 2 S was transformed to carbon disulfide (CS 2 ), an important solvent currently used to dissolve heavy hydrocarbon deposits. The results indicated that SOFCs with a LSV anode might be used for the processing of sour natural gas (containing CH 4 , H 2 S, etc.) in which both electricity and high value chemicals (i.e., sulfur and CS 2 ) are produced simultaneously.