A Comparison of the H_3PW_(12)O_40/MCM-41 and HY Zeolite for Alkenylation of p-Xylene with Phenylacetylene

摘要

The initial activity, selectivity, and especially catalytic stability of mesoporous MCM-41 supported phosphotungstic acid (HPW) prepared by ultrasonic-assisted impregnation (UAI) method and the HY zeolite were contrastively investigated for alkenylation of p-xylene with phenylacetylene in a fixed-bed continuous flow reactor. N_2 adsorption-desorption, FT-IR, X-ray diffraction (XRD) and NH_3 temperature-programmed (NH_3-TPD) desorption characterization techniques were employed to explore the relationship of catalyst nature and catalytic performance in alkenylation. Results illustrate that the as-prepared HPW/MCM-41 catalyst exhibits notably superior catalytic activity, selectivity and stability to microporous HY zeolite, ascribed to its well-ordered mesoporous architecture, appropriate acidic sites and high dispersity of HPW phase.