Highly selective Me-ZSM-5 catalyst for methanol to propylene (MTP)

•Impregnation including 5 steps results in the high surface area and crystallinity.•The Mn incorporation in HZSM-5 catalyst adjusts the acidity better.•Mn-ZSM-5 catalyst represents the highest reported propylene selectivity.•Methanol conversion over Mn-ZSM-5 catalyst is 100% for whole time on stream.

Methanol dehydration over ZSM-5 catalyst produces propylene and varied hydrocarbons. We synthesized high silica HZSM-5 catalyst (Si/Al = 200) and impregnated with different promoters (P, Mn, Mg and Cs). SEM, XRD, BET, FTIR and NH3-TPD techniques characterized the catalysts. The parent catalyst is stable during the impregnation and the modified catalysts include high crystallinity (>92%) and BET surface area (>303 m2/g). Mn incorporation adjusts the acidity better (strong/weak ratio = 1). Mn-ZSM-5 and P-ZSM-5 catalysts represent the highest methanol conversion (100%) and long term life time (120 h) as well as the parent catalyst. Mn-ZSM-5 catalyst represents the highest reported propylene selectivity (58.4%) over ZSM-5 catalyst in the methanol to propylene (MTP) reaction. The developed catalyst has high potential to apply in the industrial scale MTP process.