2008 Volume 51 Issue 3 Pages 157-164
Steam reforming of dimethyl ether, DME, over Cu/ZnO/ZrO2 and γ-Al2O3 mixed catalysts prepared by the extrusion technique was investigated. The catalysts were characterized by BET, pore-size distribution measurements, N2O chemisorption, powder X-ray diffraction, and SEM-EDX analysis. The effect of reaction temperature on catalyst life time was investigated. Steam reforming of DME over the extruded catalyst proceeded above 623 K. The major reaction products were H2 and CO2 with relatively small amounts of CO and CH4. DME steam reforming was not restricted by the equilibrium limitation of DME hydration to CH3OH, suggesting that CH3OH produced was subsequently reformed into H2 and CO2 over the catalyst. The catalyst suffered from thermal deactivation at higher temperatures; mainly caused by a reduction in Cu dispersion in the Cu/ZnO/ZrO2 catalyst. Incorporation of ZrO2 into Cu/ZnO may stabilize Cu dispersion and increase the stability of the extruded catalyst for long-term operation.