Effect of Phosphorus Addition on the Performance of Hierarchical ZSM-11 Catalysts in Methanol to Propene Reaction

Hierarchical ZSM-11 zeolite (SiO 2 /Al 2 O 3 = 65) was found to be an efficient catalyst in Methanol to Propene (MTP) reaction. The catalytic activity of ZSM-11-based catalysts was studied in MTP reaction, and the effect of phosphorus (P) addition has been comprehensively investigated. XRD, N 2 adsorption–desorption, NH 3 -TPD and Py-FTIR analyses reveal that the addition of P has a remarkable influence on the physicochemical properties of the catalysts. With the incorporation of P, the Brønsted acid sites decrease significantly, but the Lewis acid sites are almost preserved. Reaction results indicate that propene selectivity is obviously improved by P addition, and the highest propene yield (20.35 wt%) is obtained over 0.2ZAlPO catalyst. Based on the characterization and reaction results, it can be concluded that the appropriate concentration and strength of acid sites on 0.2ZAlPO catalyst with maintained MEL structure results in the enhanced propene selectivity and stability. Graphical Abstract