Search

Abstract: Polysulfone (PSf)/poly (isobutylene-alt-maleic anhydride) (PIAM) nanofiltration membranes were modified by changing the coagulation bath with various concentrations of glutaraldehyde cross-linked Chitosan solutions. Further the membranes were treated with 0.1N NaOH solution in order to achieve the hydrolysis of PIAM. The morphological changes of the membranes were determined using scanning electron microscope. The blending of PSf/PIAM membrane, the incorporation of Chitosan (CS) molecules in membrane matrix and the hydrolysis of PIAM in the membrane upon alkali treatment were studied by Attenuated Total Reflectance Infra Red (ATR-IR) spectroscopy. The hydrophilicity of modified membranes was measured using the contact angle analyzer. The pressure and time dependent pure water flux of modified PSf/PIAM/CS membranes were measured and compared with PSf/PIAM membranes (after alkali treatment). The antifouling property of membranes was determined using Bovine Serum Albumin (BSA) protein rejection studies. The modified membranes showed improved hydrophilicity and reduced pore size. The order of rejection of membranes for various electrolytes was Na2SO4 >MgSO4 >NaCl at minimum pressure of 0.2MPa TMP. The antifouling property of modified membranes increased with an increase in the composition of Chitosan in coagulation bath and membrane M-0.8 showed a maximum fouling resistance ratio of 74%. [Copyright &y& Elsevier]

Abstract: The major breakthrough in the preparation of thin film composite (TFC) membrane via interfacial polymerization technique has resulted in tremendous achievements in producing a membrane with a right combination of flux and salt rejection, and generating huge interest in industrial sectors. Over the past decade, there have been intensive and continuous efforts in the development of TFC membrane, both from the industry and academia with the interests to further improve the membrane productivity and selectivity as well as its tolerance against chlorine, solvent, fouling, etc. On basis of a brief introduction of the development history of TFC membranes, this paper reviews the recent research progress of the TFC membrane science and technology, particularly in the fields of water-related separation processes. Reviewing the research progress is imperative and necessary in order to provide an insight for the future development and perhaps open a door to extend the applications to other more challenging areas. [Copyright &y& Elsevier]

Abstract: Submerged ultrafiltration process was studied for treatment of refinery wastewater using PVDF hollow fiber membranes. The membranes were prepared via the phase inversion method by dispersing LiCl·H2O and TiO2 in the dope to study the effects of surface properties on membrane performance. The comparison of the performance and morphology was conducted on prepared PVDF composite membranes with various LiCl·H2O and TiO2 contents. The hollow fiber membranes were characterized by field emission scanning electron microscope (FESEM) and energy dispersive x-ray (EDX), average pore size and effective porosity measurements, contact angle measurement, permeability and rejection test. Maximum results were observed for membrane hydrophilicity, membrane porosity and average pore size when the TiO2 concentration was 1.95%. It was also found that interactions between the membrane surface and suspended solid constituents strongly influenced the membrane fouling. The maximum flux and rejection of refinery wastewater were 82.5L/m2 h and 98.8%, respectively, when the PVDF composite membrane with TiO2 content of 1.95% is used at pH=6.9. [Copyright &y& Elsevier]