Catalytic Combustion of C3H8 on Pt Coated Monolith†

Abstract

Abstract Three different catalysts consisting of Pt catalyst coated ceramic monolith having differing catalyst surface concentrations have been utilized to investigate the combustion of CaHg/air mixtures at inlet temperatures of 700–730 °K as a function of CaHs/air ratios. Catalytic combustion is self-initiated at these inlet temperatures even when the fuel/air ratio is quite lean, Analyses of NO, NOx, CO, CO2, and HC in the exhaust gas stream reveal that good conversion of fuel as well as CO to CO2 can occur catalytically without producing excessive NOx. The maximum combustion efficiency achieved was 99·9998% (calculated from combustion inefficiency measurements) at CaHg/air = 0·0152, inlet temperature of 719 K, and a residence time of 12 ms and the emission indexes, g pollutant/kg fuel, of NOx, HC, and CO were 0·042, 0, and 0·222, respectively. Prior to successful product application to gas turbine engines certain significant engineering/design obstacles must be evaluated and/or eliminated, such as cold start, transient operation (control requirements), life time, as well as physical volume requirements.