A facile route to synthesize mesoporous ZSM-5 zeolite incorporating high ZnO loading in mesopores

Mesoporous ZSM-5 zeolite incorporating ZnO in mesopores has been synthesized with a simple route. The commercial H-ZSM-5 (Si/Al = 50) was first treated with NaOH solution to induce a partial desilication, which can introduce a large number of intracrystal mesopores, and the ZnO nanoparticles were successfully incorporated in the mesopores with wet impregnation method. Characterizations of XRD, UV–visible absorption spectra, TEM and N2 adsorption were taken to analyze the locations of ZnO nanoparticles. The mesopores can load more than 15% ZnO with the size of about 20 nm, which can only reduce the mesopore surface area and volume, whereas, micropores are remained and cannot be blocked by the loaded ZnO particles.

The BET total surface areas and mesopore surface areas decrease in linearity as the ZnO contents increase from 0% to 20%, whereas, the micropore surface areas remain around 200 m2/g, indicating that the ZnO nanoparticles are mainly located in the mesopores of HZOH even the ZnO contents higher than 20%.Figure optionsDownload as PowerPoint slideHighlights
► Mesoporous ZSM-5 zeolite was synthesized with the desilication method by NaOH solution.
► The nanosized ZnO was introduced in the mesopores by the wet impregnation method.
► The mesopores can load more than 15% ZnO with the size of about 20 nm.
► The ZnO nanoparticles only reduce the mesopore surface area and volume.