Synthesis Of Magnetic Graphene Oxide Nanocomposites And Adsorption Performance For Sulfadiazine

In our work,two different graphene oxide magnetic composite materials were prepared.magnetic graphene composite is via electrostatic self-assembly method,another was prepared by a one-pot solvothermal method.And the chemical composition 、crystal structure、morphology and magnetic property of the magnetic adsorbent were analysed.This article selected sulfadiazine as the goal pollutant,adsorption performance of composite materials and magnetic oxide graphene regeneration effect analysis of magnetic oxide graphene were analysed.The research contents are as follows:First of all, magnetic graphene composite with core-shell structure was prepared by the method of electrostatic self-assembly.Based on magnetic graphene oxide with characterization, it is concluded that the magnetic particle exists in the form of Fe3O4 crystalling phase, composite surface contains rich oxygen functional groups;Magnetic graphene the composite material has good core-shell structure;Magnetic properties of the GO/Fe3O4 particles were investigated. Magnetic saturation intensity of 27.7 emu · g- 1.The adsorption kinetics was well described by the pseudo-second order kinetics model, Langmuir mode was better fit for the result of the adsorption equilibrium experiment.Thermodynamic parameters indicated that the process of sulfadiazine adsorbed by GO/Fe3O4 was spontaneous endothermic physical.With concentration of Na Cl in the solution increasing, the GO/Fe3O4 adsorption of sulfadiazine showed the trend of gradual reduce to increase 。Adsorption mechanism revealed that the π-π conjugate interaction was the dominated interaction forces in the adsorption process mentioned. Adsorbent regeneration study, under methanol as solvent the temperature of 80 ℃, 1 h conditions to regenerate saturated adsorbent regeneration By using soxhlet extractor.Adsorbent recycled after 8 times, adsorption amount is 84% of the original,Sulfadiazine recovery remain at around 80%.Second,In order to further improve the stability of the composite materials,composite components have stronger binding force,chemical bonding principle was used to recombination magnetic particles and graphene oxide,At the same time chitosan were used to modified magnetic particle surface.a ternary nanocomposite, graphene oxide/magnetite chitosan(GO/CS/Fe3O4), was synthesized through a one-pot solvothermal method. Based on graphene oxide/magnetite chitosan characterization, it is concluded that the magnetic particles exists in the form of Fe3O4 crystalling phase,there were plenty of oxygen-containing functional groups located on the surface of the nanocomposite. Magnetic particle uniformdistribution in the surface of graphene oxide, and the magnetic particle surface are covered with chitosan; Magnetic saturation intensity of 20.91 emu · g- 1.The adsorption kinetics was well described by the pseudo-second order kinetics model,Langmuir mode was better fit for the result of the adsorption equilibrium experiment.Thermodynamic parameters indicated that the process of sulfadiazine adsorbed by GO/CS/Fe3O4 was spontaneous endothermic physical. Adsorption capacity and the surface charge of the nanocomposite under the different value of pH were chosen to investigate the adsorption mechanism, which revealed that the π-π conjugate interaction and electrostatic attraction were dominated interaction forces in the adsorption process mentioned. With concentration of Na Cl in the solution increasing, the GO/CS/Fe3O4 of sulfadiazine adsorption capacity increased gradually.Adsorbent regeneration study, ability of methanol on the interpretation of sulfadiazine is best, under the temperature of 80 ℃, 0.5h conditions to regenerate saturated adsorbent regeneration.Adsorbent recycled after 8 times, adsorption amount is 91.7% of the original, keeping good adsorption capacity,Sulfadiazine recovery remain at around 80%.Studies have shown that magnetic graphene oxide and magnetic graphene oxide chitosan showed excellent adsorption on sulfadiazine. By contrast, magnetic graphene composite preparation process is simple, graphene oxide/magnetite chitosan adsorbent stability is better, both have good application prospects.