Chemical Engineering & Technology, Vol.39, No.4, 715-722, 2016
Adsorption of Nickel Ions on Oxygen-Functionalized Carbons
The adsorption of nickel(II) ions on pristine and wet-chemically oxidized microporous carbons is studied. The nature and acidity of the resulting oxygen functional groups are characterized by temperature-programmed desorption and point of zero charge measurements. The maximal nickel ion adsorption capacity of the resulting high-affinity Langmuir-type adsorption equilibrium is strongly influenced by the oxidative pretreatment. At maximum, loadings of 7.5 wt% could be obtained for carbons showing oxygen content of 12.5 mmol g(-1). A linear correlation of the ion uptake with the surface oxygen content could be deduced. In a kinetic study, it could be proved that the uptake of nickel at room temperature is a slow process and that the time for adsorption is independent of oxygen content, carbon type, and nickel loading.
Keywords:Carbide-derived carbon;Ion adsorption;Nickel adsorption;Oxygen-functionalized carbons;Surface treatment