含有分子筛次级结构的多孔支撑体的制备及表征

Preparation and Characteration of the Porous Support Possessing Secondary Building Units

摘要:

以丝光沸石（MOR）分子筛为原料，采用冷等静压-固态粒子烧结法制备分子筛膜用含有MOR次级结构的多孔支撑体。分别采用氮气渗透通量、开孔孔隙率、抗压强度、平均孔径及孔径分布、热膨胀系数、X射线衍射（XRD）、拉曼（Raman）光谱、扫描电镜（SEM）等表征多孔支撑体的性能。结果表明，氮气渗透通量、开孔孔隙率随煅烧温度升高和煅烧保温时间延长而降低；抗压强度则与之相反；平均孔径随煅烧温度升高变大，孔径分布随原料粒径分布变窄而变窄；保留了原料中MOR的四、五和八元环等次级结构；次级结构的存在及较低的热膨胀系数（10-6℃-1级别）使得在其表面制备的MOR分子筛膜具有良好的耐热稳定性。

Abstract:

The supports with secondary building units (SBUs) for zeolite membrane was prepared by MOR zeolite powder using the cold isostatic pressing-solid state sintering method. The propertities of the porous suppport were examined by N2 permeance, open porosity, cross-bending strength, mean pore size and distribution of pore size, the coefficient of thermal expansion, X-ray diffraction (XRD), Raman spectroscopy and scanning electron microscopy (SEM). The results were that with the rising of sintered temperature and the extending of calcination holding time, N2 permeance and open porosity decreased, but the cross-bending strength increased. The mean pore size became big with the sintered temperature increasing and the distribution of pore size was narrow with a narrow distribution of starting material particle size. The SBUs of 4, 5 and 8 membrane ring of MOR were kept in the supports. The MOR membrane prepared on the support had good thermostability because of the SBUs and low coefficient of thermal expansion (at the level of 10-6 ℃-1).