Catalytic performance of La-modified HZSM-5 catalysts for methanol to gasoline reaction

La-modified HZSM-5 catalysts were prepared by impregnation method, and characterized by XRD, NH₃-TPD, Py-FTIR and N₂ adsorption/desorption techniques. Their catalytic performance in methanol to gasoline (MTG) reaction was evaluated in a fixed-bed tubular reactor at 350℃ and WHSV of 4.74 h^-1 under ambient pressure. The results show that the introduction of La decreased the amount of acid sites, specific surface area and pore volume of HZSM-5 catalyst. The catalyst with La loading of 4% exhibited the best catalytic performance in MTG reaction, over which the lifetime and gasoline yield increased from 12 h and 52.69% to 16 h and 59.28%, respectively. In addition, the selectivity to aromatics in gasoline decreased markedly by 18% with increasing La content.