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A cellulose-based anion exchanger (Cell-AE) bearing the sN + HR 2 Clfunctional group was prepared through graft copolymerization of glycidyl methacrylate onto cellulose (Cell) in the presence of N,N′-methylenebisacrylamide as a cross-linker using benzoyl peroxide as the initiator, followed by amination and hydrochloric acid treatment. The adsorbent was characterized by infrared spectroscopy, scanning electron microscopy, surface area analysis, thermogravimetry, and potentiometric titrations. Batch experiments were performed to evaluate the adsorption efficiency of Cell-AE toward V(V) ions in aqueous solutions. The maximum removal was observed in the pH range of 4.0-6.0. The adsorption process achieved more than 99.6% V(V) removal from an initial concentration of 25.0 mg/L. Adsorption kinetic data were described by pseudo-second-order equation. The equilibrium data fitted very well with the Langmuir model, and the maximum adsorption capacity of Cell-AE toward V(V) was found to be 197.75 mg/g at 30 °C. Over 96.0% desorption of V(V) was achieved with 0.1 M NaOH solution.

This paper describes the adsorption properties of Cu(II) ions from aqueous media by 4-ethyl thiosemicarbazide (ETSC) intercalated organophilic calcined hydrotalcite (OHTC). Elemental analysis, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric–differential thermogravimetric (TG/DTG) studies have helped in characterizing the adsorbent. The effects of various factors like adsorbent dose, pH, initial concentration, and contact time were studied. The pH study indicated that Cu(II) has a good adsorption potential at pH 5.5. The adsorption of metal ion remained constant after 4 h. The pseudo-second-order model was the best fit to describe the adsorption kinetics. The FTIR spectroscopy revealed that both amino and thiocarbonyl groups in ETSC–OHTC are responsible for Cu(II) removal. The Freundlich model described the adsorption results very well, and the K F value was found to be 21.38 at 303 K. Electroplating industry wastewater was used to test the adsorption efficiency toward Cu(II) removal. The recovery (∼95.0 %) of Cu(II) ion from the loaded adsorbent was possible with 0.01 mol·kg–1 HCl solutions. Many successive adsorption/desorption cycles were achieved without any noticeable change in the adsorption capacity.