|
|||||
|
|
Kinetics of methane oxidation on Pt catalysts in the presence of H2S and SO2 |
|
| Authors: | V. Dupont J.M. Jones A. Westwood |
| Affiliation: | a School of Process, Environmental and Materials Engineering, Department of Fuel and Energy, The University of Leeds, Leeds LS2 9JT, UK b Thermal Engineering and Fluids Division, Beijing Institute of Civil Engineering and Architecture, Beijing 100044, China c Johnson Matthey, Catalytic Systems Division, Royston SG8 5HE, UK |
| Abstract: | The kinetic parameters of the lean oxidation of CH4 over alumina and ceria-alumina supported platinum catalysts in the presence of H2S and SO2 were derived in a stagnation point flow reactor at atmospheric pressure and at temperatures up to  . A novel methodology similar to that of plug-flow reactors was devised to calculate the best-fit values for frequency factors and activation energies for the proposed heterogeneous gas-solid reactions of oxidation. Doping the N2-diluted CH4/air reactant flow with H2S or SO2 concentrations between 30 and  had a significant promotional effect on the methane combustion rate. Al2O3 and CeO2/Al2O3 were shown to be inert with respect to the oxidation of CH4 to CO2, and also in the oxidation of SO2 to SO3 in air. Pt catalysed the oxidation of CH4, SO2 and that of H2S. A temperature window of conversion of SO2 to SO3 on the Pt-supported catalysts was found experimentally, and could be of practical use in combustion exhaust clean-up techniques. The repeated use of the foil resulted in a slight ageing effect for Pt/Al2O3. The presence of ceria in the washcoat helped prevent the loss of activity in CH4 oxidation by mitigating the extent of sintering of the Pt particles upon ageing. One-step and two-step chemical reaction mechanisms are proposed for the CH4 and the SO2 lean oxidations, respectively. |
| Keywords: | Catalytic Oxidation Methane Sulphur Kinetics Modelling |
| 本文献已被 ScienceDirect 等数据库收录！ | |