Effective removal of heavy metals from aqueous solutions by orange peel xanthate

Preparation of orange peel xanthate and its adsorption behaviors of five heavy metals (Cu ²⁺ , Cd ²⁺ , Pb ²⁺ , Zn ²⁺ and Ni ²⁺ ) were studied. FTIR spectra, Zeta potentials and TG analysis were used to characterize prepared orange peel xanthate. Effects of various parameters including equilibrium pH, initial metal ion concentration and adsorption time on the adsorption processes for the five metal ions were investigated. It was found that for all five metal ions, the adsorption isotherms agreed Langmuir model very well and the maximum adsorption capacities of Cu ²⁺ , Cd ²⁺ , Pb ²⁺ , Zn ²⁺ and Ni ²⁺ were obtained as 77.60, 76.57, 218.34, 49.85 and 15.45 mg/g, respectively. All adsorption processes can attain equilibrium within 20 min and kinetics was well fitted by psesudo-second order equation. It is proposed that the adsorption mechanism was complexation.