Facile fabrication of polymeric quaternary ammonium salt hydrogel by radiation for dyes removal from aqueous solution

Abstract

The effluents containing various dyes from the process industries raise esthetic problems and cause toxic impacts on aquatic and human life. Thus, the dye effluent must be adequately treated before being discharged into water-bodies. A cellulose-derived quaternary ammonium salt was treated by radiation to form hydrogel structure. The radiation dose effects on gel fraction and swelling properties were investigated. The hydrogel structure was characterized by IR and SEM analyses. The Zeta potential values at different pH were all greater than +30 mV, which indicating that the hydrogel possessed enough electrostatic attraction force to anionic ions. The adsorption behaviors of the polymeric quaternary ammonium salts hydrogel (PQH) towards methyl orange (MO), Congo red (CR), and Coomassie brilliant blue (CBB) are discussed. The pseudo-second-order mode well fitted the adsorption kinetics for all three dyes. The increasing order of the initial adsorption rate h0 was MO > CR > CBB. The Langmuir model well described the adsorption isotherms were well described by with the maximum adsorption capacity for MO, CR, and CBB being 628.93, 427.35, and 617.28 mg/g, respectively. HCl was used to regenerate the dye-loaded-hydrogel. The adsorption-desorption test demonstrated the good reusability of this hydrogel. Also, the PQH has selective adsorption of MO from RhB/MO mixing solution.