A novel ligand based dual conjugate adsorbent for cobalt(II) and copper(II) ions capturing from water

Organic-inorganic based conjugate materials are important in nanotechnology based on the high functionality and stable complex formation with target metal ions at optimum conditions. In this study, anew ligand immobilization based dual and tunable conjugate adsorbent was investigated under specific solution acidity for detection and removal of Co(II) and Cu(II) ions. In this detection system, notable color changes (intense pi-pi transition) and absorbance spectral intensity of the conjugate adsorbent for Co(II) and Cu(II) were observed at pH 8.0 and 5.2, respectively. Under the optimum conditions, the calibration graphs were the linear and detection limit which were 0.52 and 0.41 mu g/L for Co(II) and Cu(II), respectively. The removal efficiency was carried out as a function of solution pH, initial metal ions concentration, and co-existing diverse ions. Sorption equilibrium was well fitted to Langmuir isotherms and determined sorption capacity was 205.33 and 199.20 mg/g for Co(II) and Cu(II), respectively. The adsorbent proved to have an efficient ability for continuous monitoring and removal of Co(II) and Cu(II) ions, even on-site and in situ chemical analyses. The adsorbent was eluted with dilute HCl acid and simultaneously regenerated into its original form. However, several cycles were reused with slight decrease in sorption capacity compared with the initial capacity. Therefore the conjugate adsorbent can be used as cost-effective materials and is a potential candidate for the selective detection and removal of Co(II) and Cu(II) ions from wastewater. The proposed adsorbent was compared with other materials and applied to the analysis and removal of Co(II) and Cu(II) ions from several water samples with satisfactory results. (C) 2014 Elsevier B. V. All rights reserved.