Iono-molecular Separation with Composite Membranes I. Preparation and characterization of membranes with polysulfone matrix

The fast development of these methods in the recent years has been possible due to new materials developing, the boom of nanomaterials in the development of composite and hybrid materials and also due to developing of new techniques and technologies. This paper presents the composite membranes based on polysulfone and performance nanomaterials: polyaniline and magnetic nanoparticles synthesis and characterization. Composite membranes (PSf-PANI and PSf-magnetite) have been produced by phase inversion by immersion - precipitation from a polysulfone in N- methyl pyrrolidone dispersion solution in which were dispersed polyaniline or magnetic nanoparticles. The prepared composite membranes were morphologically and structurally characterized using techniques and specific measurments: FT-IR, SEM, AFM, UV VIS, DSC, dielectric spectroscopy, solvents permeation and bovine serum albumin retention. Membranes pore size indicate their use in micro and ultrafiltration (12% in the case of PSF membrane and 12% for PSf - PANI) or in the field of microfiltration and membrane sensor, 12% for magnetite - PSF membrane. The results show that water flows at 3-4 bar pressure, are increasing in the order: PSf membrane < PSf -magnetite membrane <PSf-PANI membrane. While for alcohols, the dependence is reverse: PSf membrane > PSf-magnetite membrane > PSf-PANI membrane. In the case of alcohols flow, hydrocarbon chain has influence on flows and this correlates with hydrophily of membranes. Following bovine serum albumin retention tests, PSf-PANI membrane has the best performance (R>95%), which correlates with the higher permeate flows.