Graphene Oxide-Crospolyvinylpyrrolidone Hybrid Microspheres for the Efficient Adsorption of 2,4,6-Trichlorophenol

Abstract

Microspheres of the graphene oxide and crospolyvinylpyrrolidone composite (GO-PVPP) were prepared via suspension polymerization and investigated for the adsorption of 2,4,6-trichlorophenol (2,4,6-TCP) from wastewater. The microspheres were thoroughly characterized using scanning electron microscopy, infrared spectroscopy, N2 physisorption, elemental analysis, X-ray diffraction, and thermogravimetric analysis. The GO-PVPP microspheres comprised GO sheets on the surface and demonstrated good thermal stability, good swelling rate, and excellent adsorption capacity of 2,4,6-TCP (up to 466.77 mg/g). The adsorptions were determined as a function of pH, temperature, adsorbent loading, adsorption time, and initial content of 2,4,6-TCP in the solutions. The sorption kinetics was satisfactorily modeled using the pseudo-second-order rate equation, and the sorption equilibrium can be described using the Freundlich model. The 2,4,6-TCP adsorption by GO-PVPP was shown to be endothermic and spontaneous. The reusability of GO-PVPP was also demonstrated by the adsorption and desorption cycles.