Adsorption of copper and zinc onto carbon material in an aqueous solution oxidized by ammonium peroxydisulphate

The aim of the present work was to evaluate and compare of carbon materials for the ability to eliminate Cu (II) and Zn (II) ions from water. Ammonium peroxydisulphate ((NH4)2S2O8)-treated carbon material (Ox-CM) was prepared from the combustion of forest branches and was compared with raw carbon material (CM). The adsorption isotherms and the influence of contact time, initial pH, and ionic strength for the adsorption of Cu (II) and Zn (II) were determined. The results of this work show that the removal ratios of Cu (II) for CM and Ox-CM after 2 h were 8.7 and 94.2%, respectively; and, those of Zn (II) for CM and Ox-CM after 2 h were 7.8 and 89.9%, respectively. The values of the parameters obtained for Cu (II) were based on the Langmuir isotherm saturated adsorption amount (Q0) and the adsorption equilibrium constant (KL): 27.47 mg/g and 0.4556 L/mg on Ox-CM; 3.66 mg/g and 0.2099 L/mg on CM, respectively. Those of Q0 and KL for Zn (II) were as follows: 22.52 mg/g and 0.4978 L/mg on Ox-CM; 3.07 mg/g and 0.5560 L/mg on CM, respectively. In this work Ox-CM provided the optimal level of adsorption for Cu (II) and Zn (II) ions.