Irradiated Polysulfone Membranes by Gamma Ray

MARTIN MASUELLI; N. ARIEL OCHOA; JOSE MARCHESE; MARIANO GRASSELLI

Montpellier

Congreso; Euromembrane 2009; 2009

Introduction. Polysulfone (PSf) membranes with two different pore size were irradiated by g-ray, for obtain hydrophilic membranes [1]. Synthesis. PSf (Udel 3500P) 10 and 15% p/p respect to solvent were dissolved in N,N-Dimethylformamide (Sigma). Then they were mixed with 10% of polyvinylpyrrolidone (85kDa, Stanton) and casting on support (FO2430, Fraudemberg). Finally, the casting solutions were coagulated in water at 25ºC. Irradiation.  A heterogeneous solution of methanol/water (1/1 in vol.) were prepared. Then a portion of Membrane (aprox. 374 cm2 of area), was inmersed into these solution and all system was degassed with N2. The membranes were irradiated to 25ºC in irradiation cell (GammaCell de 60Co, Centro Atómico Ezeiza, CONEA), with a dose of 6.92 kGy, and rate of 0.906 kGy/hs. After irradiation, the membranes were washed with methanol/ water solution, pure methanol and finally dry at 40ºC during 24 hs [2]. Characterization. The membranes were characterized by liquid-liquid displacement porosimetry (ISCO-500D syringe pump), contact angle measurement (Micromeritics Anglometer) and hydraulic permeability (Minitan S cell and Millipore peristaltic pump) [3]. Discussion. The increment of PSf content on casting solution decreased the pore size. Radii pore distribution (fig.1) evidence a increment of mean pore size when the membranes were irradiated. The same behaivour was observed when hydraulic permeability measurements (m/sPa) was done on both no modified and modified membranes (10PSf10 11.76x10-10, 15PSf10 9.91x10-10 and 10PSf10Irr 57.17x10-10, 15PSf10Irr 14.80x10-10, respectively). Contac angle of PSf was 78 degree, while 10PSf10Irr and 15PSf10Irr membranes shown contact angles about of 75 and 74 degree, respectively. Conclusion. This membranes present high hydrophilicity and great pore size. The irradiation process drive to rupture of bonds via free radicals, generating pore more great and functional group with afinty to water like -COOH,-SO3H. References. [1] Effect of hydrophilicity on fouling of an emulsified oil wastewater with PVDF/PMMA membranes. N. Ochoa, M. Masuelli, J. Marchese. Journal of Membrane Science 226(2003)203-211. [2] Immobilized metal ion affinity hollow-fiber membranes obtained by the direct grafting technique. Mariano Grasselli, Agustín A. Navarro del Cañizo, Silvia A. Camperi, Federico J. Wolman, Eduardo E. Smolko, Osvaldo Cascone. Radiation Physics and Chemistry 55 (1999) 203-208. [3] SPC/PVDF membranes for emulsified oily wastewater treatment. Martin Masuelli, José Marchese, Nelio A. Ochoa. Journal of Membrane Science 326 (2009) 688–693.