中文摘要：

首次将氢氧化钠-氟硅酸铵复合改性应用于甲醇制丙烯（MTP）催化剂的制备中。采用X射线衍射（XRD）、X射线荧光光谱（XRF）、N2吸附-脱附、透射电镜（TEM）、NH3程序升温脱附（NH3-TPD）等测试技术对改性前后HZSM-5分子筛催化剂的晶体结构、元素组成、织构性质、酸性质等进行了表征。结果表明，采用氢氧化钠-氟硅酸铵复合改性不仅可以提高催化剂的介孔孔容，还能有效调变催化剂的酸性。复合改性方法成功克服了单纯碱处理容易破坏分子筛的骨架结构、单纯氟硅酸铵改性因受扩散限制仅限于修饰分子筛外表面的缺点。改性后HZSM-5分子筛催化剂在MTP反应中的诱导期大大缩短，在常压、反应温度为470℃^、甲醇质量空速（WHSV）为2 h-1的条件下，初始丙烯选择性高达43%。此外，复合改性后HZSM-5分子筛在MTP反应中的稳定性大幅改善，催化寿命延长至本体样品的3倍。

英文摘要：

A sequential modification by sodium hydroxide （NaOH） and ammonium hexafluorosilicate （（NH4）2SiF6） solution was used for preparing MTP （methanol to propylene reaction） catalyst for the first time. The parent and modified samples were characterized by diverse techniques including powder X-ray diffraction （XRD）, X-ray fluorescence （XRF） spectroscopy, N2 adsorption-desorption, transmission electron microscopy （TEM）, and NH3 temperature-programmed desorption （NH3-TPD）. The effect of modification on the physicochemical properties, such as framework, chemical composition, texture, and acidity, were investigated in detail. The results showed that the mesopore volume of the zeolite catalyst increased significantly fol owing sequential NaOH and （NH4）2SiF6 modification. The acidity was also modulated effectively. The composite modification method successful y overcame the disadvantages associated with individual simple alkali and （NH4）2SiF6 treatments. For instance, using a simple alkali treatment would destroy the framework of the zeolite easily, whereas using a simple （NH4）2SiF6 treatment would only modify the external surface of the zeolite owing to the limited diffusion of the ammonium hexafluorosilicate molecule. When used in MTP reaction, the induction period＆amp;nbsp;of the composite modified sample was greatly shortened, and the initial selectivity for propylene increased to 43%under the fol owing operating conditions：T=470 ＆#176;C, p=0.1 MPa （pMeOH=50 kPa）, and weight hourly space velocity （WHSV）=2 h-1. Moreover, the composite modified zeolite catalyst exhibited significantly improved stability, and the catalytic lifespan was triple that of the parent sample.