Preparation And Characterization Of Three Dimension RGO/FeOOH Composite And Its Adsorption Property Of U(?)

Uranium is both the key radionuclides in nuclear fuel and the main component of spent fuel reprocessing. Separating uranium from high-level radioactive liquid can not only recycle the uranium resource but also reduce the uranium pollution. At present, adsorption is widely used to remove the heavy metal from radioactive liquid.Graphene and its composites is expected to be a new adsorbent due to its large surface area, high porosity, good temperature resistance, good radiation resistance, high stability and environmentally friendly property. In this thesis, the main results are listed as follows:First, the preparation of graphene oxide:the improved method of hummers was used to prepare graphene oxide which contained a large number of oxygen functional groups on its surface. Graphene oxide could dissolve stably in solutions for a long time with the shape of a single or less layer that conducive to the preparation of graphene oxide composite materials.Second,preparation and characterization of three dimension RGO/FeOOH composite: three-dimensional network structure of RGO/FeOOH composite was prepared by hydrothermal method via the synergies between graphene oxide sheets and the reduction of Fe(?). The quality ratio of 38 to 1 for FeSO4 and graphene oxide,6-hours reaction time and 90? bath temperature were the optimum condition, which could successfully prepare RGO/FeOOH composite hydrogels that had intact morphology and homogeneous images. The characterizations indicated that this composite materials had nano-pore structure. Many FeOOH nano-particles appeared on the sheets of the composites and these nano-particles' sizes ranged from 200 nm to 300 nm.Third, the uranyl adsorption experiments of three-dimensional RGO/FeOOH composite materials:The effect of the amount of Fe2+, ClO4-, pH were investigated in this study. Results indicated that the adsorption capacity of the composites decreased with the increasing of the amount of reducing agent; The adsorption behavior of the composite material didn't affect by ClO4- which indicated that the adsorption process was not just physical adsorption but was the chemisorptions.When pH was 5.5, the adsorption temperature was 15?, adsorption time was 4 hour, the initial concentration of uranyl solution was 100 ppm, the maximum adsorption capacity was 115 mg/g; The adsorption isotherms indicated that the materials'adsorption kinetics was consistent with the double Langmuir model curve; The selective adsorption experiment results indicated that RGO/FeOOH composite had good selectivity for uranium.