Electrosorption Of RhB On Graphene-titanium Electrode

Dyestuff industry in China has developed rapidly in recent years. A lot of dye waste water is discharged into the environment in the process of dye production, which cause serious harm to human body health. In the case of RhB,this study use electric adsorption technology to deal with RhB dye wastewater. As a new type of nanometer materials, graphene (Gr) with high conductivity, larger specific surface area, good chemical stability and excellent properties. These characteristics provide a good basis for the study of graphene in the field of electro adsorption. In this study, we examinned the best optimized conditions of the Gr/Ti electrodes for RhB adsorption performance, and investigated the reuse of the electrodes. According to the above research purpose, this study had carried out the following work.(1)With the improved Hummers method, a new electrode (Gr/Ti) was prepared by graphene and titanium (Ti) substrate. At the same time, Cyclic voltammogram, SEM and FTIR spectrum were used to characterize Gr and Gr/Ti.(2)The testing parameters of electrosorption were initia concentration of electrolytes, potential, temperature and initial pH. The results indicated that the maximum adsorption capacity reached 44.46 mg·g-1 under the condition of -600 mV, pH of 7.3,293 K and 0.01 M electrolyte. And it was 3.12 times than open circuit in 10 mg·g-1 RhB solution.(3)Interrelated analyses concluded that under the condition of optimization, The adsorption process has a good value of adsorption thermodynamics and adsorption kinetics. Thermodynamic parameters were enthalpy, entropy and Gibbs free energy. And electrosorption of RhB on Gr/Ti was found to be endothermic and spontaneous.(4)When the regeneration voltage was-10 V, the regeneration efficiency reached more than 90%. And it was still more than 65% after 10 consecutive electrosorption/regeneration cycle.This study achieved good results in the new electric adsorption system, which provides the theoretical support for the practical applications and mass production of graphene.