Study On The Graphene Oxide In Adsorption Of Methylene Blue

Great volume, high content of organic pollutants, low content of nitrogen and phosphorus, dark colority, strong alkalinity, and the big change of water quality are the major characteristic of water that is polluted by organic dyes, which is difficult to be treated. The popular methods to treat the wastewater include flocculation settlement, ion exchange, membrane separation and chemical oxidation, electrolytic method, biological method and adsorption, and so forth. Nowadays, carbon nano-composite materials,like fullerenes, carbon nanotubes, graphene and graphene oxide are becoming more and more important for the adsorption of water that contains dyes.Graphene is the name given to a flat monolayer of carbon atoms tightly packed into a two-dimensional(2D) honeycomb lattice, and an increasing number of researchers are pay attention to graphene because of its excellent thermal, electrical and mechanical properties. However, the strong van der Waals force between the sheets of graphene makes them easy to agglomerate, and results of the limited application. Based on the existing problems in the research of graphene, the modified Hummers’ method is used to prepare graphene oxide(GO) in this paper and X-ray diffraction(XRD) analysis indicates that graphite has been successfully intercalated and exfoliated. X-ray photoelectron spectroscopy(XPS) and Fourier Transform Infrared Spectoscopy(FT-IR) analysis suggest that lots of oxygen containing functional groups appear in the surface of GO. Raman spectra(Raman) analysis demonstrates that the defects of GO is strongly higher than graphite. Thermal Gravimetric Analyzer(TGA) analysis further indicates it. Scanning electron microscope(SEM), Transmission electron microscopy(TEM) and Atomic force microscopy(AFM) are taken to characterize GO, and the analysis suggest that few-layer of GO have been prepared.In order to explore the adsorption ability of GO to methylene blue(MB) under the same condition. Many different experimental scheme research platforms are set up, and different kind of samples are got through shock absorption and centrifugalseparation, then ultraviolet-visible(UV-Vis) is used to test the the concentration of MB after adsorption. 1) The test results indicate that UV-Vis has good performance and the actual demands can be satisfied. 2) GO has the best uptake ability of MB when compared with the same mass of graphite and bamboo carbon under the same condition. 3) The adsorption ability of GO decreases with the increase of quality under the same condition Without reach the adsorption equilibrium; The adsorption capacity of GO increases with the increase of time, but the increasing amplitude decreases on the whole; The adsorption capacity of GO increases with the increase of concentration of MB under the same condition Without reach the adsorption equilibrium, too; The adsorption ability of GO do not change much under the condition of different temperatures; The adsorption ability of GO increases with the increase of alkalinity of MB solution under the same condition; The adsorption behavior fits well to Langmuir adsorption isotherm and Freundlich adsorption isotherm and pseudo-second order kinetic equation.