以高岭土为原料的复合分子筛的水热合成

HYDROTHERMAL SYNTHESIS OF COMPOSITE MOLECULAR SIEVE USING KAOLIN AS A RAW MATERIAL

以高岭土为原料,补加一定量的硅酸钠,利用水热法合成高稳定性复合分子筛。采用X射线衍射、Fourier变换红外光谱、扫描电子显微镜、透射电子显微镜和N2物理吸附等手段对样品进行表征,并考察样品的热稳定性和水热稳定性。结果表明:样品中有介孔和微孔双重结构,所合成分子筛的比表面积为550.43m2/g,平均孔径为2.74nm,样品经800℃焙烧3h、100℃水热处理10d后,介孔结构仍然存在。

A composite molecular sieve with high stability was synthesized by the hydrothermal method using kaolin as a raw material.For the synthesis process,certain amounts of sodium silicate were added.The samples were characterized by the X-ray diffraction,Fourier transform-infrared spectroscopy,scanning electron microscopy,N2 physical adsorption,and transmission electron microscopy.Additionally,the thermal and hydrothermal stabilities of the sample were evaluated.The results show that the synthesized sample has a both mesoporous and microporous structure with a specific surface area of 550.43 m2/g,and the average pore size is circa 2.74 nm.The mesoporous structure of the resulting sample is still retained after calcination at 800 ℃ for 3 h or hydrothermal treatment at 100 ℃ for 10 d.