Abstract:
Graphene oxide (GO) has excellent adsorption performance for dyes in water, but the effect of its oxidation degree on the adsorption performance and mechanism of composite materials has not been fully studied. Three kinds of graphene oxide (GO) with different oxidation degrees were synthesized by the Hummers and then compounded with polyvinyl alcohol (PVA) to synthesize three kinds of GO/PVA aerogels. The oxidation degree of GO was characterized by infrared spectroscopy (FTIR), elemental analysis (EA) and thermogravimetric analysis (TG). Using methylene blue (MB) as a simulated pollutant, the effect of GO oxidation degree of GO/PVA aerogels on MB adsorption performance under different solution pH, adsorption time and initial concentration was investigated through static adsorption experiments. The absorption mechanism of GO/PVA aerogels had been explored by adsorption kinetics model, model of adsorption isotherm and adsorption thermodynamic model. The results show that the adsorption behavior of GO/PVA aerogels on MB is slightly affected by pH. Increasing the oxidation degree of GO can significantly improve the adsorption capacity and adsorption speed of GO/PVA aerogels. And the adsorption sites on aerogel can be increase by improving the oxidation degree of GO , which is conducive to adsorption. In addition, the degree of GO oxidation has no obvious effect on the adsorption mechanism of GO/PVA aerogels.