钛硅分子筛晶胞参数计算方法研究

利用X射线衍射技术（XRD）对钛含量不同的系列钛硅分子筛（TS-1）的晶体结构进行研究。通过调节XRD测试的仪器参数，确定了最优试验条件，建立了利用Rietveld全谱拟合计算钛硅分子筛晶胞参数的方法。通过计算发现：原料中钛摩尔分数低于2.5 %时制备的分子筛的晶胞参数随钛含量增加呈线性增加，推断分子筛制备时部分钛进入骨架；原料中钛摩尔分数为2.5 % ~ 8.0 %时制备的分子筛的晶胞参数基本不变，推断制备时钛摩尔分数高出2.5 %的部分不再进入分子筛骨架。

INVESTIGATION OF CALCULATION METHOD FOR TITANIUM SILICALITE ZEOLITE STRUCTURE

X-ray diffraction (XRD) technique was used to characterize the titanium silicalite (TS-1) zeolites with various amounts of titanium and the optimal test conditions were obtained by adjusting the instrument parameters. The calculation method for lattice parameters was established by the Rietveld full spectrum fitting technology for the XRD patterns. The calculation results suggest that when the mole fraction of the titanium in the raw material is less than 2.5 %, the lattice parameter of the TS-1 zeolite increases linearly with the titanium content, indicating part of the titanium in the raw materials entering into the framework of the TS-1 zeolite. The lattice parameter is basically unchanged above 2.5 % mole fraction. It can be inferred that the excessive titanium atoms（a part of the 2.5% above）do not enter into the framework of the TS-1 zeolite.