| Energy is the basic problem of human development.With the consumption and pollution of fossil energy,people begin to develop new clean energy.Nuclear power uses uranium,thorium,and other heavy nuclear elements to produce energy by fission to produce steam,so that gases such as SO2 and CO2 are not produced.However,China is a country with less uranium reserves,the total content of uranium in natural seawater over thousands of times the global uranium reserves,development and utilization of marine resources,has an important significance to alleviate the shortage of nuclear fuel in china.In addition,a large amount of uranium containing wastewater will be produced in the treatment of nuclear fuel,which will not only lead to environmental pollution,but also lead to the loss of a large amount of uranium resources.Adsorption is the most effective method for the treatment of heavy metal ions in aqueous solution.Therefore,the preparation of adsorbent materials has become the focus of the study on seawater uranium extraction in recent years.In this paper,agarose as the basic object,modified agarose material using hydrogen peroxide and ferrous sulfate co pyrolysis reaction,and the use of SEM,TEM,infrared spectrum and XRD test were found 5% mass fraction of modified agarose gel material with interpenetrating network structure better,because the hydrogen peroxide redox reaction,combined with large the number of C-O-C key amplitude in the molecule decreases and Fe agarose and agarose particles reduced by agarose gel material absorption and mechanical strength.It was found that the modified agarose material had the best adsorption performance at pH=6,and the maximum adsorption capacity was 82mg/g,which was 60% higher than that of the original agarose.Adsorption accords with Langmuir isothermal adsorption model and quasi two stage adsorption kinetic model.The gel material with ion permeability,so the modified agarose of uranyl ion selection performance is poor,but has a high sensitivity in low concentration solution,the uranyl ion concentration of 50 g/L and materials on uranium removal rate can reach more than 99.8%.In order to solve the problem of poor selectivity of materials,the ammonium nitrate was grafted onto the surface of the agarose material and ammonium chloride was used as the graft initiator.Using SEM,TEM,infrared absorption spectroscopy and other characterization to prove the synthesis process and synthesis principle.The adsorption properties of inquiry ammoximation agarose,ammoximation agarose best adsorption pH=7,the maximum adsorption capacity of 241.56mg/g,and the adsorption accord with Langmuir adsorption model and the quasi two level adsorption dynamic model.It was found that the strong acid desorption agent had the best desorption performance for the material,and the adsorption capacity was only 93% lower than that of the raw material by using the method of nitric acid desorption and the adsorption experiment of the 5 cycle.In order to improve the preparation of agar carbohydrate adsorption materials,agarose gel electrophoresis was used to enhance the adsorption performance of the composite.The experimental results show that the acid buffer solution pH=4.6 has the best effect on the adsorption,and the adsorption rate of 2 minutes can be achieved by using the 100mg/g uranium solution for single adsorption performance test.The results show that the adsorption rate of the solution is.In the competition of uranyl ions and copper ions,copper ions can not be adsorbed by the adsorbent in the gel.In this method,the adsorption capacity of 100 mL uranium solution was decreased,and the removal rate was 82%. |
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