Steam reforming of dimethyl ether over Cu–Ni/γ-Al2O3 bi-functional catalyst prepared by deposition–precipitation method

Cu–Ni/γ-Al2O3 catalysts with different metal contents for dimethyl ether steam reforming (DME SR) were prepared by the method of deposition–precipitation. Characterization of specific surface area measurement (BET), X-ray diffraction (XRD) and hydrogen temperature-programmed reduction (H2-TPR) revealed that nickel improved the dispersion of copper, increased the interaction between copper and γ-Al2O3, and therefore, inhibited the sintering of copper. Ammonia temperature-programmed desorption (NH3-TPD) showed that metal particles could occupy the acid sites, leading to the decrease in acid amount and acid strength of Cu–Ni/γ-Al2O3 catalyst. Kinetic measurements indicated that γ-Al2O3 is vital for DME SR and a higher content of γ-Al2O3 in catalyst was needed. The addition of nickel suppressed the water gas shift (WGS) reaction. Initial durability testing showed that the conversion of DME over Cu–Ni/γ-Al2O3 catalyst was always almost complete during the 30 h experimental reaction time. Therefore, Cu–Ni/γ-Al2O3 could be a potential DME SR catalyst for the production of hydrogen.