中空纤维担载Al2O3-SiO2复合膜的研制

采用溶胶-凝胶法在α-Al2O3中空纤维载体上制备了Al2O3-SiO2复合膜,并对复合膜的制备条件及稳定性进行了研究.利用SEM和EDS对复合膜的微观形貌及化学组成进行了分析.结果表明,所制备的担载复合膜表面完整、无缺陷.气体渗透实验进一步说明,复合膜具有一定的气体选择性,在0.1 MPa下对H2/N2的分离因子为3.03,表明气体通过膜的扩散以Knuen扩散传质为主.用等温氮气吸附实验测定了非担载膜的孔径大小和分布,其比表面积为294.85 m2/g,总孔容为0.28 mL/g,最可几孔径小于3 nm.

Preparation of Al2O3 - SiO2 composite membranes supported on Al2O3 hollow fiber

Al2O3-SiO2 composite membranes supported on Al2O3 hollow fiber were prepared by sol-gel method.The pseparation condition and stability were studied.The microstructure and chemical composition of composite membranes were investigated by SEM and EDS.It was found that the membranes were defect-free.Gas permeation testing showed that the membranes were of gas selectivity,and the separation factor of hydrogen to nitrogen was 3.03 at 0.1 MPa.Which means the gas diffusion through the membranes was mostly governed by Knudsen diffusion mechanism.The most probable pore diameter of an unsupported composite membranes was less than 3 nm,its specific surface area was 294.85 m2/g and the total pore volume was 0.28 mL/g.