Abstract：Boron-silicon MFI zeolites with good crystallinity were prepared by hydrothermal synthesis method. Alkali treatment to them was carried out with Al3+ addition to achieve the purpose of boron removal and aluminum insertion. Hierarchical molecular sieves with different pore structures and acid properties were obtained. The prepared sieves were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), physical adsorption, NH3 temperature programmed desorption (NH3-TPD) and other means. And the catalytic performance of zeolite samples for methanol to propylene (MTP) reaction was evaluated in a fixed bed reactor. Combined with the MTP reaction evaluation and the thermogravimetric analysis of the molecular sieve samples after the reaction, it was found that the selection of appropriate NaOH concentration in the alkali treatment process to zeolites was conducive to the improvement of propylene selectivity and the reduction of carbon deposition for MTP reaction catalyzed by the prepared sieves. The results of long-term running test showed that the methanol conversion was higher than 99% and the propylene selectivity remained stable during a stable operation of 600 h with methanol space velocity of 3 h-1. The coke deposition amount of the deactivated catalyst was about 40% mass fraction, indicating the good carbon capacity of the catalyst.
XU Zipu,LIU Min,GUO Xinwen. Simultaneous Optimization of ZSM-5 Pore Structure and Acidity to Prepare High Performance Catalysts for MTP Reaction[J]. Chemical Reaction Engineering and Technology, 2022, 38(5): 385-393.
