A double network gel as low cost and easy recycle adsorbent: Highly efficient removal of Cd(II) and Pb(II) pollutants from wastewater

A high strength of polyving alcohol/polyacrylic acid double network gel (PVA/PAA gel) adsorbent was successfully prepared by a simple two-step method in this study. The gel adsorbent possessed the advantages of low cost and high adsorptivity for heavy metals in solution. The maximum uptake capacities of PVA/PAA gel were 194.99 mg/g for Pb(II) and 115.88 mg/g for Cd(II) inferred from the Langmuir model at 303 K. At the concentration levels of Pb(II) < 150 mg/L and Cd(II)< 100 mg/L, the Pb(II) and Cd(II) could be completely adsorbed, showing a great potential of removing heavy metals from wastewater. Simultaneously, the PVA/PAA gel adsorbent exhibited an excellent reusability. Even in the fifth cycle, the removal efficiencies of both Pb(II) and Cd(II) remained nearly 100%. Significantly, the gel adsorbent displayed a satisfactory performance of removing heavy metals in actual industrial effluent. The results reveal that the double network gel can be considered as a potential candidate for practical application. (C) 2015 Elsevier B.V. All rights reserved.