Syngas CO cleaning for fuel cell applications by preferential oxidation: Catalyst development and reactor design

Abstract

Proton exchange membrane fuel cells are widely employed in micro-combined heat and power cogeneration (micro-CHP) systems and the feed to them should be essentially free of CO. CO preferential oxidation is an effective method for deeply removal of the CO content in synthesis gas. A series of Pt/γ-Al2O3 catalysts are made and tested for their CO cleaning capabilities. The catalyst is prepared from chloroplatinic acid and γ-Al2O3 powder by normal or ultrasonic impregnation. Catalyst performance is investigated in a micro-reactor system. Effects of Pt loading, ultrasonic processing, CO space velocity, oxygen to CO ratio and reaction temperature on catalyst performance are studied. A CO preferential reactor for a kilowatt-scale CHP system is designed and tested. A special catalyst loading pattern is tried to maintain a uniform bed temperature distribution and high CO conversion. A CO concentration of <10 ppm is achieved when the CO concentration in the gas feed is 0.45%. © The Author 2012. Published by Oxford University Press.