Xuping Zhou

Characterization of Zr-based MCM-41 mesoporous molecular sieves obtained by microwave irradiation or hydrothermal method

Zr-based MCM-41 mesoporous molecular sieves (ZrMCM-41) were successfully synthesized by microwave irradiation method and hydrothermal method, respectively. The obtained samples were characterized by XRD, TEM, FT-IR and N2 physical adsorption. The results show that the samples synthesized by the two different methods both possess typical hexagonal mesoporous structure of MCM-41 and high specific surface areas (over 800 m2/g). After calcination at 750°C for 3 h or hydrothermal treatment at 100°C for 6 days, the mesoporous structure of the samples still retained, however, the mesoporous ordering is poor. Under the comparable conditions, the reaction time required in the synthesis of ZrMCM-41 by microwave irradiation method was greatly reduced, and microwave irradiation method is eco-friendly and is easy to operate.

Preparation of mesoporous zirconium incorporated MCM-48 solid acid catalyst and its catalytic activity for alkylation of phenol with tert-butyl alcohol

Abstract Zirconium incorporated mesoporous MCM-48 solid acid catalysts with the different Si/Zr molar ratios were prepared by modification with H2SO4 and NH4NO3 solution, respectively. Their physicochemical properties were characterized by XRD, TEM, NH3–TPD and N2 physical adsorption. The catalytic performances of these catalysts were investigated by using the alkylation reaction of phenol and tert-butyl alcohol as the target reaction. The results reveal that the SO42−/ZrMCM-48 and H-ZrMCM-48 catalysts still maintained the cubic mesporous structure of MCM-48, but the mesoporous ordering decreased. Under comparable conditions, the catalytic activity of SO42−/ZrMCM-48(25) solid acid catalyst is the highest among all catalysts. The lower reaction temperature is favorable for formation of the 2,4-DTBP and the 4-TBP is easily formed at the higher reaction temperature.