Study on the reaction performance of methanol to aromatics over Zn/HZSM-5 catalysts with alumina

The present paper investigated the effect of Zn modified HZSM-5 catalysts on the reaction performance of methanol to aromatics with the presence of alumina. The catalysts were characterized by BET, XRD, Py-FTIR, NH₃-TPD, and H₂-TPR techniques, respectively. The experimental result demonstrated that the introduction of alumina produced mesopores in the HZSM-5 catalyst and strengthened the stability of Zn species on the surface of the catalyst. The introduction of Zn species broke the structure of HZSM-5 zeolite and changed the surface acidity of the catalyst. In addition, Zn species might contribute to the dehydrogenation reaction of MTA. Meanwhile, the subsequent aromatization process of olefins was impressed. Within the scope of this study, the maximum value of aromatic yield (C_6~11) reached 21.0% when the loading of Zn was 0.5%. The aromatization of methanol is at the control of coke on the catalyst. However, the regenerated catalyst exhibited a higher aromatic yield.