B04-B07

[B04] Control of hydrocarbon oligomerization in phosphorus modified CHA zeolite and its prolonged catalytic lifetime in methanol-to-olefin reaction

○Nao Tsunoji¹, Ryota Osuga², Toshiyuki Yokoi² (1. Hiroshima University, 2. Tokyo Institute of Technology)

Keywords:CHA zeolite, phosphorus modification, methanol to olefin reaction

Prolonged catalytic lifetime in the methanol to olefin (MTO) reaction was achieved by the direct phosphorus modification of CHA zeolite using tetraethylphosphonium as a phosphorus modifying agent (P-MA). The P-MA was firstly introduced into the zeolite pore system during the hydrothermal synthesis system, then its decomposition by calcination caused to form phosphorus oxide interacting with zeolite framework. A combinational analytical method of the CHA zeolite catalysts before and after the MTO reaction revealed that the inhibited excess oligomerization of hydrocarbon, tuned by the phosphorus modification, resulted in a prolonged catalytic lifetime.