CO₂ reforming of dimethyl ether to produce hydrogen over La₂O₃/γ-Al₂O₃ catalyst

In this paper, La₂O₃/γ-Al₂O₃ catalysts with different La loading were prepared by incipient wetness impregnation method.This paper investigated the influence of La loading and reaction temperature on catalytic performance for the carbon dioxide reforming of DME. The catalysts were characterized by X-ray diffraction (XRD), BET surface area, transmission electron microscopy (TEM), thermogravimetry and differential thermal analysis(TG-DTA). The results showed that the La₂O₃/γ-Al₂O₃ with 15% La loading gave the best catalytic performance at 550 ℃.The selectivity of H₂ and CO were 93.3% and 76.04%, and the conversion of CO₂ and DME were about 85.4% and 100%, respectively, while the selectivity of byproduct CH₄ is only 6.3%. This 15% La₂O₃/γ-Al₂O₃catalysts had more symmetrical distribution of particle size,larger specific surface area and more proper pore structure, and it kept stable performance during 4 h test. As a result, the catalyst average coking rate was only about 1.387 5 mg/(g·h).