仿生制备SiO2分离膜的实验

以表面活性剂十六烷基三甲基溴化铵(CTAB)在溶液中的自组装胶束为有机模板,对无机前躯体正硅酸乙酯(TEOS)的水解缩聚过程进行调控,于SiO2 无机膜中复制出了具有自组装体形状的三维孔结构。孔径分布测定结果表明优化物料条件下制备出的非担载SiO2 膜具有 1. 8nm的最可几孔径,平均孔径为 5. 3nm。对比传统的sol gel制膜方法,其孔径分布不受灼烧条件的影响。该膜的广角XRD分析结果表明组成介孔壁面的SiO2 为非晶型结构,该膜的小角度XRD分析结果进一步表明,膜内介孔道的排列形式为三维空间上的无序网络结构。将优化物料条件下的混合物旋涂于多孔Al2O3 陶瓷载体上,进一步制备出了SiO2 分离膜,该膜的SEM表征和气体渗透性能测定结果表明其完整性能较好。

Synthesizing new silica membrane by biomimepic technology

Based on templating technique, CTAB templated silica membranes were prepared repeatedly under (optimized) experimental conditions. The results of pore size distribution determination show that the silica membrane has modal pore size in 1.8 nm, which corresponds to the size of CTAB micelles, and its averaged pore diameter is 5 3 nm. Compared with the membrane prepared with sol-gel process, its pore size distribution wasn′t influenced by the highest calcining temperature. Broad-angle X-ray diffraction pattern result shows that silica composing channel walls is non-crystalline structure, and only one broad diffraction peak appears in the narrow-angle XRD pattern of silica membrane, which further indicates that its pore channels construct a non-organized 3D network.