Preparation Of Functional Reduction Graphene And The Research Of Its Adsorption Performance

Graphene is a new kind of carbon adsorption material raised in recent years, it was new two-dimensional carbon material constituted by the sp2 hybridization of carbon atoms. Because of its’ unique properties, such as large specific surface area, super heat conductivity, good chemical stability and excellent mechanical properties, this material aroused great interest by scientists in the fields of physics 、 chemistry and materials, in the meantime, it also raised a upsurge studying graphene all over the world.Although graphene has so many advantages, there are many difficult problems in the process of its application, such as: graphene’s hydrophobic; graphene, which structure is integrity, has higher chemical stability; graphene is easy to reunion; and so on. All these problems limit the development of the application of graphene. Scientists’ researchs showed that these problems can be solved through through surface functionalization of graphene.The functionalization of graphene was that, we modified the graphene surface through increasing reactive group, improving the hydrophilicity, reducing the force between the layers, so we can achieve the goal that dispersed graphene into nano level. In this paper, we used ethylenediamine as reductant to restore and modify graphene oxide, and prepared functionalized graphene. The main work is as follow:(1) In this paper, according to the method of improved the Hummers, we successfully prepared the GO. And using ethylenediamine as reduction and modifier, we restored GO, made its’ surface functionalized modification, and got the functional reduction graphene(FRG). With FRG as adsorbent, we adsorbed the heavy metal ions, Cr6+. The results showed that under the condition of low pH, FRG had excellent adsorption performance; removal rate can reach 98%. What is more, FRG not only adsorbed Cr6+, but it could restore the high toxic Cr6+ into low toxic of Cr 3+, so it could reduce the harm to the environment.(2) Using FRG as adsorbent, we studied the adsorption performance of reactive brilliant blue KN-R, which is anionic dye. The results showed that at room temperature、pH of 1、adsorbent additive quantity of 0.5 g/L were its’ optimal reaction conditions. In this condition,the removal rate could reach 95%. In addition, we compared the adsorption performance of reactive brilliant blue KN-R on different graphene made by different methods. Through comparing, we found absorption efficiency of reactive brilliant blue KN-R on FRG was best.We also compared adsorbing effect of reactive brilliant blue on GO and FRG for graphene,and results showed that adsorbing effectthe of reactive brilliant blue KN-R on FRG was better than the adsorbing effect of graphene oxide. And fitting the experimental data to the dynamic equation and adsorption isotherm models, we can see that the adsorption of reactive brilliant blue KN-R on FRG conformed to pseudo secondary dynamic model, the adsorption isotherm conforming to Langmuir model.(3) Using functional reduction graphene(FRG) as adsorbent, we discussed its adsorption performance of cationic dye methylene blue in water. The results showed that the FRG adsorption effect of MB on FRG was not good than KN-R on FRG, it also needed a long time(6 h) when the adsorption reached equilibrium.The removal of MB was also associated with the pH of the solution. With the increase of pH, the effect gradually got better.