Synthesis of Hierarchically Porous H[P, Al]‐ZSM‐5 and its Catalytic Performance in Coupling Transformation of Methanol with 1‐Butene.

Hierarchically porous P substituted HZSM‐5 (H[P, Al]‐ZSM‐5‐AT‐0.05 M) was successfully synthesized by isomorphous substitution method with introduced P atoms into ZSM‐5 zeolite frameworks followed by alkali treatment. H[P, Al]‐ZSM‐5‐AT‐0.05 M was characterized by XRD, ICP‐OES, SEM, FT‐IR, N2 adsorption‐desorption, NH3‐TPD, XPS, Py‐IR, and TG‐DTA, respectively. The surface area, pore volume, particle size and P/Al (molar ratio) are 328 m2.g−1, 0.23 cm3.g−1, 563 nm and 0.027, respectively. The catalytic performance of H[P, Al]‐ZSM‐5‐AT‐0.05 M in coupling reaction of methanol with 1‐butene was investigated in the fixed‐bed reactor. On the condition of reaction temperature at 500°C under atmosphere pressure, the main product is propylene with the selectivity and yield of 33.7% and 31.0%, respectively. Hydrogen transfer index was calculated to 0.24. Moreover, its diffusion limitation was investigated with the self‐etherification of benzyl alcohol reaction. The value of Thiele modulus (η) and effectiveness factor (ϕ) are 0.08 and 16.9, respectively. The scheme of isomorphously substituted method of introducing P into ZSM‐5 framework and catalytic performance over H[P, Al]‐ZSM‐5 and H[P, Al]‐ZSM‐5‐AT‐0.05 M in coupling methanol with 1‐butene. P substituted HZSM‐5 is treated with NaOH solution to form mesoporous zeolites. The result shows that H[P, Al]‐ZSM‐5‐AT‐0.05 M exhibited higher catalytic stability, higher apparent reaction rate, effectiveness factor and lower content of diffusion limitation in coupling of methanol with 1‐butene to propylene reaction. [ABSTRACT FROM AUTHOR]