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采用水热法,在Na_2O-K_2O-Al_2O_3-SiO_2-HMBr_2-H_2O体系,一步法快速合成了具有T型和L型两种结构特征的T-L复合分子筛,通过XRD、N2吸附-脱附、SEM-EDX、TEM、FT-IR和TG-DTG等手段,对合成样品的物理化学性质进行了表征.结果表明:所合成的分子筛是球形L型分子筛镶嵌在椭圆体T型分子筛一侧,形成的1~2μm左右的双结构复合分子筛;孔道性质表征说明其具有微孔和介孔的多级孔道结构,微孔平均孔径为0.82 nm,介孔的孔径主要分布在3.8 nm左右.通过对阳离子比R=K_2O/(K_2O+Na_2O)影响因素进行分析,获得T型、L型及T-L复合分子筛的转化规律,R的大小在0.3~0.5 nm范围内可以合成结晶度高的T-L复合分子筛.
A series of TL composite molecular sieves with T-type and L-type structures were successfully synthesized by one-step hydrothermal method in Na 2 O-K 2 O-Al 2 O 3 -SiO 2 -HMBr 2 -H 2 O system by XRD, N2 adsorption-desorption and SEM- EDX, TEM, FT-IR and TG-DTG were used to characterize the physicochemical properties of the synthesized samples. The results showed that the synthesized zeolite was spherical L-type zeolite inlaid on one side of elliptic T-type zeolite, ~ 2μm. The characterization of the pore structure shows that it has a multi-stage pore structure with micropores and mesopores, the average pore diameter of micropore is 0.82 nm, and the pore diameter of mesopore is mainly distributed at about 3.8 nm. The cation ratio R = K_2O / (K_2O + Na_2O), the transformation rules of T-type, L-type and TL composite zeolites were obtained. The high molecular weight TL composite zeolite can be synthesized in the range of 0.3-0.5 nm.