Characterization of APTES-modified montmoriilonite and adsorption of Sr ( Ⅱ )
3-氨丙基三乙氧基硅烷改性蒙脱石的表征及其对Sr（Ⅱ）的吸附研究

As a functional coupling agent,3-aminopropyl triethoxysilane (APTES) plays an extremely important role in clay functionalization.In this study,the structure and surface property of montmorillonite modified by APTES with different ion exchange capacity (1.0CEC,1.5CEC,2.0CEC,2.5CEC,3.0CEC and 4.0CEC) was characterized by Fourier transform infrared spectroscopy,X-ray diffraction analysis,and Scanning Electron Microscopy,respectively.The adsorption properties of Sr (II) by APTES was also analyzed.The results indicated that sorption capacity increased with increasing pH (1.0~10.0),and reached balance after 24 h.The maximum adsorption capacity of APTES-modified montmorillonite was 3 times that of raw montmorillonite.Moreover,the desorption rates of APTES-modified montmorillonite was very low.The characterization results of XRD,SEM and FTIR revealed that APTES was intercalated into the layer of montmorillonite.The mechanism of Sr (II) adsorption was mainly coordination.