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A sorbent based on polyvinyl formal and polyacrylic acid for the removal of heavy metals from water solutions

The characteristics of a hybrid pH-sensitive hydrogel sorbent based on polyvinyl formal and polyacrylic acid, synthesized by radical copolymerization, were investigated in the process of removing copper (II), zinc (II) and nickel (II) metal ions from water solutions. A high efficiency of the extraction (up to 96%) of metal cations (Cu(II)>Zn(II)Ni(II)) was reveled at their concentration of up to 250 mg L–1 in the pH range of 5.8 to 6.8. The experimental data were analyzed by using theoretical kinetic models and adsorption isotherms. The developed polymer sorbent was shown to be promising for removing heavy metals, even after its multiple regeneration.