Synthesis of Ga2O3/HZSM-5@cubic ordered mesoporous SiO2 with template Pluronic F127 to improve its catalytic performance in the aromatization of methanol

Abstract

A composite HZSM-5@cubic ordered mesoporous SiO2 (HZ@COMS) was synthesized by an acidic sol–gel coating method with template Pluronic F127. HZ@COMS and Ga loading HZ@COMS (Ga/HZ@COMS) were applied in methanol to aromatics (MTA). The existence of the silica shell reduces the acid amount and acidity of HZSM-5, which decreases in the formation of coke on the catalyst. At the same time, such silica shell with 3D hierarchical and cubic ordered mesopores improves the diffusion of seeds and coke precursor. As a result, the catalytic performance of HZSM-5 was improved effectively with the introduction of silica shell in such structure. Making a comparison with HZSM-5, the longevity of HZ@COMS increased from 10 to 42 h and the selectivity of BTX increased from 44 to 49%. After Ga’s loading, the cubic ordered mesopore offered a nanoscale reactor in the reformation of C9+ hydrocarbons, which further improves the longevity of catalyst (54 h) and the selectivity of BTX (50%). Ga/HZ@COMS presents good ability in the regeneration ability in MTA.