The effect of hydrothermal pretreatment on the catalytic performance of Zn/HZSM-5 catalysts for ethylene aromatization reaction

The catalysts were characterized using XRD, N2 physical adsorption-desorption, NH3-TPD, Py-FTIR, XPS, and TG techniques. The effect of hydrothermal pretreatment on the catalytic performance and stability of the catalyst was investigated using ethylene aromatization as a probe reaction.

The results showed that the Zn/HZSM-5 catalyst exhibited excellent catalytic performance after high-temperature hydrothermal pretreatment. Although the conversion of ethylene slightly decreased, the catalyst lifetime significantly increased from 72 h to 216 h, while maintaining an aromatic selectivity of over 60%. It was suggested that the hydrothermal treatment enhanced the interaction between ZnO species and B acid sites, promoting the generation of ZnOH+ species.