EFFECT OF ADDITION OF DIFFERENT PROMOTERS ON THE PERFORMANCE OF PT-SN-K/AL₂O₃ CATALYST IN THE PROPANE DEHYDROGENATION

The effect of the addition of different promoters, namely, La, Ir, Re and Cs to trimetallic Pt-Sn-K/Al₂O₃ catalyst on its performance in propane dehydrogenation was studied. The reference trimetallic Pt/Sn/K and tetrametallic catalysts Pt/La/Sn/K, Pt/Ir/Sn/K, Pt/Re/Sn/K and Pt/Sn/Cs/K were prepared by sequential impregnation of g-alumina support. The catalysts were characterized by TPD and TPR tests. Catalytic performance tests were carried out in a fixed-bed quartz reactor for propane dehydrogenation activity and propylene selectivity under representative industrial conditions. The Pt/Sn/Cs/K catalyst showed better performances in terms of propylene yield. The performance of Pt/Sn/Cs/K catalysts was further improved by adjusting its Cs loading. The addition of Cs to Pt-Sn-K/Al₂O₃ catalyst could improve catalytic performance chiefly through modifying the nature of acidic function of the support.