以四丙基氢氧化铵(TPAOH)为模板剂、NH₄F为矿化剂,运用水热晶化法制备厚度为10~100 nm的纳米薄片状高硅ZSM-5分子筛,考察TPAOH/SiO₂摩尔比、晶化温度对纳米薄片状高硅ZSM-5分子筛制备的影响,并对其甲苯动态吸附性能进行评价。结果表明,晶化温度为90 ℃时,随着TPAOH/SiO₂摩尔比的增加,纳米薄片状高硅ZSM-5分子筛的尺寸与厚度减小,孔容与平均孔径增大。TPAOH/SiO₂摩尔比为0.35时,晶化温度的升高不影响纳米薄片状高硅ZSM-5分子筛的形貌、结晶度与孔结构。相比市售高硅ZSM-5分子筛,厚度10~20 nm、SiO₂/Al₂O₃摩尔比为305的纳米薄片状高硅ZSM-5分子筛对甲苯的动态穿透吸附容量增加约22.5 %、饱和吸附容量增加约26.8 %,且吸附曲线符合Yoon-Nelson模型。经20次重复再生后,该纳米薄片状高硅ZSM-5分子筛的甲苯吸附容量衰减低于0.5 %,展现出良好的再生使用性能。

High silica nano flake-like ZSM-5 zeolite with a thickness of 10-100 nm are successfully prepared through hydrothermal crystallization method with tetrapropylammonium hydroxide (TPAOH) as template and NH₄F as mineralizing agent.The influences of TPAOH/SiO₂ molar ratio and crystallization temperature on the preparation of nano flake-like high silica ZSM-5 zeolite are studied,and its dynamic adsorption performance for toluene is evaluated.The results indicate that under 90℃,with the increasing TPAOH/SiO₂ molar ratio,the size and thickness of the nano flake-like high silica ZSM-5 zeolite prepared decreases while the total pore volume and average pore size increase.The morphology,crystallinity and pore structure of the prepared nano flake-like high silica ZSM-5 zeolite are not affected by increasing hydrothermal crystallization temperature when TPAOH/SiO₂ molar ratio is 0.35.Compared with commercial high silica ZSM-5 zeolite,the dynamic penetration adsorption capacity and saturation adsorption capacity of toluene by the as-prepared nano flake-like high silica ZSM-5 zeolite with a thickness of 10-20 nm and a SiO₂/Al₂O₃ molar ratio of 305 increase by about 22.5 % and 26.8 %,respectively,and the adsorption curves accord with Yoon-Nelson model.After the as-prepared nano flake-like high silica ZSM-5 zeolite has experienced 20 times of regeneration,its adsorption capacity for toluene only attenuates less than 0.5 %,showing a good regeneration performance.

陈伟(1989-),男,硕士,高级工程师,研究方向为大气污染治理用分子筛等多孔材料吸附剂的研究与开发,charrycechen@sina.cn