Membrane-based gas separations are becoming relevant. Ordered mesoporous silicas have uniform pore channels with a mesopore range. The mesopores are advantageous for rapid diffusion of target molecules, can be modified in a variety of ways, allowing for separation applications. We first describe the technologically scalable fabrication based upon mesoporous silica membranes on polymeric hollow fibers. Furthermore, we modify the mesopores using amine-containing polysilsesquioxane molecules. The resulting modified membranes exhibit promising permeability and selectivity in separation of CO2 from N2 or CH4. Also, the CO2 and N2 transport properties of aziridine-functionalized mesoporous silica membranes are investigated. The hyperbranched aminosilica membrane shows bi-functional gas transport property regarding humidity of gas streams.

Radioactive liquid waste has given soil & water pollution and further congenital defect to the humanity. With this regard, there are lots of interests in reducing concentration of radioactive material even if it is in low level (ppm). There are filtration driven by pressure such as ultra-filtration, nano-filtration, and reverse osmosis to separate radioactive liquid waste. Among them, Nano-Filtration membrane shows promising performance in both permeability and selectivity. Commercial nanofiltration membrane were applied to separate model solutions. Model seawater was desalinated to 6,100 ppm with flux of 90 L/ ㎡h. On the other hands, Model nuclides (Co, Cs, and Sr) solutions are separated from 10 ppm to 2 ppm, 0.23 ppm, and 0.13 ppm. Commercial nanofiltration membranes show the trade-off property between selectivity and flux.