Improved performance of hierarchical Fe-ZSM-5 in the direct oxidation of benzene to phenol by N2O

Abstract Hierarchical Fe-ZSM-5 zeolites were directly synthesized from a zeolitic synthesis system in the presence of a silane coupling agent 3-glycidoxypropyltrimethoxysilane (GPTMS). The structure and morphology of the hierarchical Fe-ZSM-5 synthesized with different amount of GPTMS were characterized by XRD, SEM, TEM, and N 2 adsorption-desorption techniques. UV–vis and NH 3 -TPD were used to investigate the state of iron species and acidity, respectively. The steaming activated hierarchical Fe-ZSM-5 were used as catalysts in the direct oxidation of benzene to phenol (BTOP) with N 2 O as oxidant, showing an improved performance in terms of both activity and stability compared to Fe-ZSM-5 synthesized in the absence of GPTMS. A comparison study on the n -butane uptakes in Fe-ZSM-5 zeolites indicated the internal mass-transfer limitations of the hierarchical Fe-ZSM-5 zeolites were significantly improved.