Removal of Basic Dye from Aqueous Solutions Using a Novel Nanocomposite Hydrogel: N-Vinyl 2-Pyrrolidone/Itaconic Acid/Organo Clay

Abstract

In this work, N-vinyl-2-pyrrolidone/itaconic acid/organo clay nanocomposite hydrogels were synthesized by free radical polymerization technique using different amounts of organo clay. Fourier transform infrared spectroscopy, X-ray diffraction, and scanning electron microscopy techniques were used for characterization of nanocomposite hydrogels and swelling, and mechanical properties of these hydrogels were investigated. Safranine-T adsorption capacities of nanocomposite hydrogels were investigated at different conditions such as pH, contact time, adsorbent dose and initial concentration of dye. The optimum pH value was found to be pH 6. According to the organo clay content, there are no significant differences in dye adsorption capacities of nanocomposite hydrogels until the clay content reaches 5 % wt. While the organo clay amount of nanocomposite hydrogels increases up to 10 % wt, dye adsorption capacities of these hydrogels significantly decrease. Adsorption processes of dye onto the nanocomposite hydrogels follow pseudo-second-order type adsorption kinetic. The equilibrium adsorption data have been evaluated using Freundlich and Langmuir Isotherm models. The results illustrated that the adsorption follows Langmuir isotherm.