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以B-ZSM-5沸石为母体,经过盐酸洗涤脱硼后,采用气固相同晶取代法制备了Ti-ZSM-5沸石.考察了制备条件如反应温度、反应时间和载气流速等对产品沸石中钛物种的配位状态和含量的影响.发现进入Ti-ZSM-5骨架中的钛含量存在一个极限值.FT-IR、UV-Vis表征技术和丙烯环氧化反应结果表明:不同气固相反应条件下制备的Ti-ZSM-5沸石具有不同的物化性质.骨架钛含量高而非骨架钛含量低的钛沸石具有较高的丙烯环氧化催化活性.
The zeolite B-ZSM-5 was prepared by gas-solid isomorphous substitution after deboronation by hydrochloric acid washing. The effects of preparation conditions such as reaction temperature, reaction time and carrier gas flow rate on the coordination states and contents of titanium species in the product zeolites were investigated. There is a limit to the amount of titanium found in the Ti-ZSM-5 framework. The results of FT-IR, UV-Vis characterization and epoxidation of propylene show that the Ti-ZSM-5 zeolites prepared under different gas-solid reaction conditions have different physico-chemical properties. Titanium zeolites with high titanium content and low titanium content have high propylene epoxidation catalytic activity.