Synthesis of ZSM-5 Zeolite by Template-Free Method
1. Research and Development Division, Shenhua Ningxia Coal Industry Grop Limited Liability Company, Yinchuan 750411, China; 2. Key Laboratory of Energy Resources & Chemical Engineering of Ningxia University, Yinchuan 750021,China
Abstract ZSM-5 zeolite was prepared by template-free hydrothermal synthesis method. The samples were characterized by NH3 temperature programmed desorption(NH3-TPD), Fourier infrared spectroscopy (FT-IR), X-ray diffraction(XRD), scanning electron microscopy(SEM) and low-temperature nitrogen adsorption-desorption technique(BET). The effects of process conditions on the structure and performance of ZSM-5 molecular sieves were investigated. The results showed that under the optimum process conditions of adding crystal seed 1% and crystallization time 24 h at 140 ℃, the relative crystallinity, crystal particle size and specific surface area of ZSM-5 zeolite product were 151%, 150 nm and 447.8 m2/g, respectively. When the ZSM-5 zeolite synthesized was applied to methanol to propylene(MTP) reaction under typical conditions, the conversion of methanol was 100%, the selectivity of propylene reached 39.5%.
