Hydrogen & Clean Fuels - Abstract
Uncatalyzed and Wall-Catalyzed Forward Water-Gas Shift Reaction Kinetics
The kinetics of the high-temperature (1070-1134 K), low and high-pressure gas-phase forward water-gas shift reaction were evaluated in an empty quartz reactor and a quartz reactor packed with quartz particles. The power law expression for the reaction rate was consistent with the Bradford mechanism and was invariant with respect to pressure. The experimental rate constant was lower than that published by Graven and Long, and slightly higher than estimates obtained using the reaction rate expression derived from the Bradford mechanism in conjunction with values of reaction rate constants obtained from the GRI database. Similar experiments conducted using a reactor composed of Inconel®600, a representative reactor shell material, exhibited greatly enhanced rates of reaction. A simple power-law rate expression was incorporated into a surface-catalyzed PFR model to correlate the results between 600 – 900 K. Palladium and palladium-copper alloy surfaces, representative of hydrogen membranes, were also shown to enhance the fWGSR rate, but not as much as the Inconel®600 surfaces.