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多级孔结构ZSM-5分子筛的合成过程复杂。利用双模板剂,通过优化晶化条件(如晶化时间与晶化温度)和Si/Al物质的量比等一步水热晶化合成了具有多级孔结构的ZSM-5分子筛,并采用XRD、N_2吸附-脱附、吡啶红外吸脱附、SEM和TEM等方法对样品的晶体结构、孔道结构、表面酸性和形貌等进行了表征。结果表明,一步法合成多级孔结构ZSM-5分子筛的适宜条件是:晶化温度160-180℃,晶化时间24-96 h,反应物组成为SiO_2/Al_2O_3/Na_2O/CTAB/TPABr/H_2O=1/x/0.4/0.05/0.12/280,(x:50-240)。其中,晶化温度160℃、晶化时间48 h和以Si/Al物质的量比50的凝胶合成的样品具有有序的介孔(平均尺寸3.60 nm)结构、较高的结晶度和较强的酸性。
Multi-stage pore structure ZSM-5 zeolite synthesis process is complicated. ZSM-5 molecular sieve with multi-stage pore structure was synthesized by one-step hydrothermal crystallization by optimizing the crystallization conditions (such as crystallization time and crystallization temperature) and the amount ratio of Si / Al. , N 2 adsorption-desorption, pyridine adsorption and desorption, SEM and TEM were used to characterize the crystal structure, pore structure, surface acidity and morphology of the samples. The results show that the optimum conditions for the synthesis of ZSM-5 zeolite with multi-stage pore structure are as follows: the crystallization temperature is 160-180 ℃, the crystallization time is 24-96 h, and the reactants are SiO 2 / Al 2 O 3 / Na 2 O / CTAB / TPABr / H 2 O = 1 / x / 0.4 / 0.05 / 0.12 / 280, (x: 50-240). Among them, the samples synthesized by the gel with the crystallization temperature of 160 ℃, the crystallization time of 48 h and the gel with the molar ratio of Si / Al of 50 had the mesoporous structure (average size 3.60 nm), higher crystallinity and Strong acidity.