چكيده به لاتين
(vinyl benzyl chloride-styrene) copolymer was synthesized via emulsion polymerization. Polymer fiber with a diameter of 250 nanometer was prepared by electrospinning method. Amination process was applied to obtain an anionic-exchange membranes with trimethylamine, triethylamine and tributylamine. Ion exchange capacity of produced membranes was measured by titration procedure. The effects of amine content was investigated, With an increase in the amounts of trimethylamine, triethylamine, and tributylamine from 1 ml to 5 ml, an increase of approximately 50 percent in ion exchange capacity of all membranes was observed and eventually reached to the constant value. Then, the performance of ion exchange membranes prepared for nitrate removal was investigated. Contact time, initial concentration of nitrate ions and type of amine agent were the parameters that were studied. The results showed that increasing the contact time increases the removal nitrate. For functionalized membranes it has been observed that the efficiency of removal of nitrate ion decreases from 75% to 45% by increasing the initial concentration of nitrate ion from 50 ppm to 100 ppm. It was also observed that the amount of removal decreased with increasing chain length in amine agents, although ion exchange capacity decreases. Increasing chain length in amine agent improves selectivity of nitrate. The scanning electron microscopy images, the structure and morphology of the fibers prepared in different proportions of solvents and in different moisture conditions, are shown. FTIR analysis shows the fixation of functional groups on the surface of copolymer fibers. In this study, Freundlich isotherm was selected as absorption isotherm and pseudo-second-order kinetic model as a desirable kinetic model.
