Implementation of Carboxymethyl Cellulose/Acrylic acid/Titanium Dioxide Nanocomposite Hydrogel in Remediation of Cd(II), Zn(II) and Pb(II) for Water Treatment Application

IN THIS study Acrylic acid/Carboxymethylcellulose/Titanium dioxide (AAc/CMC-TiO2) hydrogel nanocomposite was synthesized by free-radical crosslinking copolymerization via gamma irradiation. It was characterized using FT-IR and swelling properties. The swelling percentage increases with increasing time until reaches a certain limiting value after 6h. The synthesized nanocomposite was used as an adsorbent for remediation of Cd(II), Zn(II) and Pb(II) from aqueous solutions by the static adsorption technique. It was found that the optimum pH for the adsorption is 5 and the sorption process is carried out at fast operating time, 30-40 min, for all investigated metal ions. It was also found that the metal ions sorption capacity decreases with increasing the dosage of AAc/CMC-TiO2 from 5 to 150 mg. A progressive increase in the metal ions sorption capacity was obtained with increasing the initial metal ion concentration from 0.01 to 0.05 mol L-1 and the saturation of the sorbent active sites was done at initial metal ions concentration at 0.1 mol L-.(-1) No significant interference on the removal of Pb (II) in the presence of NaCl, Na-acetate, KCl, KNO3 and NH4Cl ions while a slight decrease in removal of Cd (II)and Zn(II) was done. The pseudo-second order kinetic model and Freundlich adsorption model describe well the kinetic and isotherm, respectively, of the adsorption process of the investigated ions.