Study on the relationship between the oxidation degree of GO and the adsorption capacity for Pb2+

Abstract

In this study, four kinds of graphite oxide (GO) with different oxidation degree have been prepared by a modified Hummers method, by changing the amount of oxidation agent KM_nO₄. To investigate the relationship between the oxidation degree of GO and the adsorption capacity for heavy metal irons, Pb²⁺ solution has been selected as a model waste water. The effects of initial Pb²⁺ concentration, solution <em>p</em>H and contact time on the adsorption capacity of series GO have been studied. It is found that the adsorption capacity does not always increase with the increasing of oxidation degree. The adsorption process of series GO for Pb²⁺ are well described by the Langmuir isotherm model, which reveales that the adsorption process is homogeneous monolayer coverage.