The preparation of hollow graphene microspheres and its application research in environmental management

Abstract

In this study, hollow graphene microspheres (GO-GE) were prepared using Gemini surfactants as hydrophobic modifiers by direct mixing method. By changing the amount of Gemini surfactants, hollow graphene microspheres with different surfactant/graphene ratios were obtained. Aromatic cyclic compounds were used as simulated pollutants to investigate the adsorption capacity of hollow graphene microspheres for simulated wastewater. The results showed that the amount of surfactant had a significant effect on the particle size, density, and hydrophilic properties of the hollow graphene microspheres. When the amount of Gemini surfactants increased, the hydrophobicity of GE-GO hollow graphene microspheres improved, and the adsorption of hydrophobic pollutants such as aromatic cyclic compounds was faster and more effective. The removal rates of toluene and benzene were as high as 84.7% and 92.6%, respectively. The order of removal rates for aromatic cyclic compounds was toluene > benzene > 4-nitrophenol > 4-nitroaniline > methyl red > methylene blue. The obtained microspheres had a long-term stability in solution, which could avoid re-polluting the water body. In addition, repeated experiments demonstrated that the microspheres had good reusability. Therefore, this type of hollow graphene microspheres may have great potential application prospects in the field of environmental wastewater treatment.