Influence of operating conditions on the removal of Cu, Zn, Cd and Pb ions from wastewater by adsorption

Nile Rose Plant was used to study adsorption of several cations (Cu2+, Zn2+, Cd2+ and Pb2+) from wastewater within various experimental conditions. The dried leaves of Nile Rose Plant were used at different adsorbent/ metal ion ratios. The influence of pH, contact time, metal concentration, and adsorbent loading weight on the removal process was investigated. Batch adsorption studies were carried out at room temperature. The adsorption efficiencies were found to be pH dependent, increasing by increasing the pH in the range from 2.5 to 8.5 exept for Pb. The equilibrium time was attained within 60 to 90 min. and the maximum removal percentage was achieved at an adsorbent loading weight of 1.5 g/50 mL mixed ions solution. Isothermal studies showed that the data were best fitted to the Temkin isotherm model. The removal order was found to be Pb2+> Zn2+> Cu2+> Cd2+. The surface IR-characterization of Nile rose plant showed the presence of many functional groups capable of binding to the metal cations.