Hierarchical SAPO-34 catalytic support for superior selectivity toward propylene in propane dehydrogenation process

Abstract

SAPO-34 molecular sieve with tuned hierarchical structure was synthesized and used as the catalytic support for propane dehydrogenation (PDH) reaction to receive propylene with high selectivity. Synthesized material was characterized by XRD, FESEM, BET, ICP, FT-IR and TPO techniques. The Pt-Sn/SAPO-34 (hierarchical and regular ones) catalysts were prepared by impregnation method, and then the catalytic activity and selectivity of the catalysts were evaluated in PDH reaction. The results were compared with commercial Pt-Sn/γ-Al2O3 catalyst at the same operational conditions. Results revealed that hierarchical SAPO-34 based catalyst was the most efficient catalyst with superior activity and high propylene selectivity. The results suggested higher stability of the catalyst with hierarchical structure during seven hours reaction. Moreover, the impact of operational conditions was investigated on the performance of Pt-Sn/hierarchical SAPO for the temperature range of 550–650 °C, weight hourly space velocity of 4 and 8 h−1 and H2/C3 molar ratios of 0.2–0.8, at normal pressure.