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Magnetic mixed-matrix membranes (MMMs) are fabricated using polysulfone (PSf) and iron oxide (Fe) for O 2 /N 2 separation. The effects of Fe nanoparticle size and content on the performance of the membranes are investigated using a novel gas permeation unit in the presence of various magnetic fields. The results indicate that the O 2 permeation is improved by adding Fe nanoparticles into the PSf matrix regardless of the particle size. Furthermore, the selectivity of PSf and PSf-Fe membranes is considerably enhanced by applying a magnetic field during the permeation experiments. The O 2 permeability and O 2 /N 2 selectivity of PSf-Fe50 MMMs in the presence of a magnetic field are higher than those of neat PSf membranes.

The wettability is the most important features of membrane, when it works as contactors. Although the membrane contactors offer many advantages over conventional contacting equipments, additional mass transfer resistance is introduced when micropores are filled with aqueous absorbents. Therefore, fabrication of superhydrophobic membrane which prevents diffusion of aqueous absorbent into membrane pores is a highly challenging task. In this work, superhydrophobic polypropylene (PP) membrane was fabricated using in situ synthesis of silica nano particles via thermally induced phase separation (TIPS) method. Flat sheet fabricated PP membranes were casted with methanolic solution containing various ratios of perfluorooctyltriethoxysilane (PFOTES)/ tetraethylortosilicate (TEOS) and then sol-gel reaction between the mixed silances was completed. The contact angle of coated membrane was reached to 168 degree, when the percentage of PFOTES/TEOS was fixed at 50% (mol/mol). Interestingly, due to the microporous structure of PP membrane, the synthesized fluorinated silica nanoparticles were observed on the surface as well as in the cross-sectional area of the membrane. Field emission scanning electron microscopy (FE-SEM) images were confirmed this point. Chemical structure of the coated membranes with 50% PFOTES was compared with pure PP membrane using ATR-IR. In order to evaluate the operational performance, coated membranes were immersed in aqueous solutions of mono ethanol amine (MEA), di ethanol amine (DEA) and pure water. In comparison with pure PP membrane, obtained results showed that the wettability of coated membranes was considerably decreased.

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