Graphene Oxide/Polyvinyl Alcohol/Fe(3)O(4) Nanocomposite: An Efficient Adsorbent for Co(II) Ion Removal

In this work, an effective nanocomposite-based adsorbent directed to adsorb cobalt (Co(2+)) ion was successfully synthesized from graphene oxide (GO), polyvinyl alcohol (PVA), and magnetite (Fe(3)O(4)) nanoparticles via a coprecipitation technique. The synthesized GO/PVA/Fe(3)O(4) nanocomposite was applied for Co(2+) ion removal with the optimized working conditions including 100 min of contact time, 0.01 g of adsorbent dosage, pH of 5.2, and 50°C of temperature. The investigation of adsorption kinetics showed that the adsorption of Co(2+) ion onto the GO/PVA/Fe(3)O(4) nanocomposite followed the pseudo-second-order kinetic model with the rate constant k(2) being 0.0026 (g mg(−1)·min(−1)). The Langmuir model is suitable to describe the adsorption of Co(2+) ion onto the GO/PVA/Fe(3)O(4) nanocomposite with the maximum sorption capacity (q(max)) reaching 373.37 mg·g(−1). The obtained results also indicated that the GO/PVA/Fe(3)O(4) nanocomposite can adsorb/regenerate for at least 5 cycles with a little reduction in removal efficiency. Therefore, we believe that the GO/PVA/Fe(3)O(4) nanocomposite could be used as a potential adsorbent for heavy metal treatment in terms of high adsorption capacity, fast adsorption rate, and recyclability.