Preparation of sulfonated poly(ethylene terephthalate) nanofibrous membranes for removal of basic dyes
In this investigation, a nanofibrous sulfonated poly(ethylene terephthalate) (SPET) membrane was prepared by electrospinning of the SPET solution in trifluoroaceticacid (TFA)/dichloromethane (DCM) mixture. The produced nanofibers had diameter ranging from 300 nm to 1 μm. The performance of this membrane's separation process was evaluated under different operating conditions. The influence of the electrospinning and filtration process parameters, such as concentration, applied voltage, deposition time, operating pressure, and filtration time on rejection of C.I. Basic Blue 3 were studied. The dead-end recirculation ultrafiltration set-up was employed. Under optimum conditions (concentration of 20% (w/v) of SPET, applied voltage of 20 kV and deposition time of 3 h) the removal of the aforementioned dye was 98%. Operating pressure has posed a significant influence on the membrane's separation performance, whereas the operating time had some effect on the separation performance. Two equilibrium adsorption isotherms: Langmuir and Freundlich were fitted to the dyes' equilibrium sorption data on SPET membrane at different feed concentrations. The Freundlich isotherm was found to well represent the measured adsorption data based on the higher coefficient of determination (r2).