Fuel, Vol.114, 178-186, 2013
A CeO2-La2O3-based Cu catalyst for the processing of coal-derived syngases via high-temperature water-gas shift reaction
A CeO2-La2O3-based Cu catalyst (referred to as CE09) has been tested in a differential reactor to measure its kinetics for the water-gas shift (WGS) reaction at temperatures of 550 degrees C and 600 degrees C which can be described by an empirical power-law rate model. The effects of CO, CO2, H2O and H-2 concentration on WGS reaction rate are determined using selected gas compositions that might be encountered in a coal based gasification system. The rates of the WGS reaction (in mol g(-1) catalyst s(-1)) over CE09 at a reaction temperature between 550 degrees C and 600 degrees C can be expressed by the a power-law rate expression which correlates well with experimental data with good accuracy: R = 10(0.724) exp(-92350/R'T)(PCOPCO2-0.06PH2-0.085)-P-0.95(1 - 1/K P-CO2(H2)/PCOPH2O) The temperature range tested in this study is well beyond the maximum operating temperature of commercially available shift catalysts. To demonstrate the application of CE09 under practical reaction conditions, its performance has been tested with a wide range of steam-to-carbon ratios in an integral reactor operating mode at an inlet pressure of 20 bar. This catalyst is shown to work well at relatively low steam-to-carbon gas ratios which could provide some practical benefits for a full-scale commercial process. (C) 2012 Published by Elsevier Ltd.
Keywords:Water-gas shift reaction;Kinetics;CeO2-La2O3-based Cu catalyst;Coal derived syngas;Steam:carbon ratio