Synthesis of core–shell ZSM-5@meso-SAPO-34 composite and its application in methanol to aromatics

Abstract

A core/shell-structured ZSM-5@meso-SAPO-34 composite catalyst was hydrothermally synthesized through overgrowing SAPO-34 molecular sieve on the external surface of ZSM-5. The catalyst was thoroughly characterized with regards to its crystallinity, morphology, elemental composition, surface area, pore volume, and acidity. The catalytic performance of the as-obtained ZSM-5@meso-SAPO-34 was tested by the conversion of methanol to aromatics reaction. ZSM-5@meso-SAPO-34 exhibited higher aromatics selectivity compared to that of pristine ZSM-5 and its physical mixture with SAPO-34. The unique catalytic synergistic behavior of ZSM-5@meso-SAPO-34 was ascribed to its effective enhancement of aromatization as a result of the acid sites on the external surface covered by the SAPO-34 shell.