疏水型SiO_2气凝胶的常压制备及吸附性能研究

Hydrophobic Silica Aerogels Prepared with Ambient Pressure Drying and Its Adsorption Properties

以多聚硅E-40为硅源,采用溶胶-凝胶法,通过表面修饰等工艺,在常压条件下制备了高气孔率的疏水性SiO2气凝胶.用扫描电镜、红外光谱1、3C,29Si核磁共振谱以及孔径分布仪,表征测试其结构和吸附特性.研究结果显示,SiO2气凝胶具有纳米多孔结构,且有较好的疏水特性,吸附性能较活性炭纤维和活性炭颗粒更为优越,再吸附容量基本不变,是一种极好的高吸附材料,具有广阔的应用前景.

A new method to prepare hydrophobic silica aerogels as effective adsorptive material was introduced. Polyethoxydisiloxanes （E-40） was used as silicon source and hydrophobic silica aerogels dried at ambient pressure were prepared via sol-gel process and surface modification. Scanning electronic microscopy, fourier transform infrared spectrometer （FT-IR）, ^13C,^29Si nuclear magnetic resonance spectra and pore size distribution measurement were used to characterize the morphology and pore structure of the silica aerogels. The adsorption capacities of the silica aerogels were also determined. The results show that the silica aerogels have a typical nano-porous microstructure with hydrophobic property. The pore size distribution is from several nanometers to dozens of nanometers. They have more excellent adsorption capacities compared with activated carbon fibres, granules of activated carbon. They are excellent adsorptive materials with wide applications.