Novel organo-mineral membranes were prepared under an external orthogonal magnetic field from suspensions by the phase inversion process. The suspensions consist of polyacrylonitrile, dimethyl sulfoxide, poly-(vinylpyrrolidone), and ferrosoferric oxide.The cross-section structures observed by SEM show that the magnetic field can control the alignment orientation of magnetic Fe 3 O 4 aggregates in the membrane. Moreover, the addition of Fe 3 O 4 can lead to the change of macrovoids in the sublayer from being tidy and perpendicular to the membrane plane to being irregular and oblique to the membrane plane. The retention rate of PAN-Fe 3 O 4 membranes to BSA decreases with the increase of Fe 3 O 4 amount and the changes in the retention rate are within a range of 2%. Furthermore, 1 wt % Fe 3 O 4 added in PAN membranes may result in a decline of the membrane permeability or the antifouling performance. But the membrane permeability and the antifouling performance then increase with the increase of Fe 3 O 4 amount from 1 to 4 wt %. Contrary to common results, the membrane permeability and the antifouling performance appear to have no direct correlation to the roughness of membrane surface obtained by AFM.

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Three kinds of membranes were prepared from suspensions containing polyacrylonitrile, dimethyl sulfoxide, polyethylene glycol and different amount of Fe3O4 by the phase inversion process. The rejection rate and the flux of membrane were investigated in the filtration of pig blood solution. SEM also studied the morphologies of fouled membranes. The permeate flux and the rejection rate decline fast in the initial several minutes and then change slowly. The magnetized membrane has a higher flux and a relative flux than the corresponding non-magnetized membrane. And the magnetized membrane containing about 3 wt% Fe3O4 has a prominent anti-fouling performance with above 52% relative flux. The results indicate that the magnetized ferrosoferric oxide-polyacrylonitrile membranes are promising in the recovery of blood proteins in the slaughterhouse effluents. In addition, the hydraulic resistance model explained results and the fouling mechanism was also given.

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