| With the rapid development of the nuclear industry and environment containing uranium wastewater emissions also increased rapidly, which on humans and the environment will cause serious harm,so how to deal with uranium containing wastewater is one of the major problems facing the management of environmental issues. At present at home and abroad on the treatment of wastewater containing uranium containing mainly include physical method, chemical method and adsorption method, but because of the method itself still exist many defects, such as high cost and easy to cause secondary pollution or adsorption quantity is not great selectivity is not good, instead of biological materials, technique and ion printed trace technology with its adsorption capacity and good selectivity is concerned gradually. The uranyl ion coordination based on the principle, starting from the construction of phosphate adsorption rich functional groups of agents, to fast and efficient wastewater treatment of uranium as the goal, the preparation of phytic acid modified fungi（PA-ZZF51） uranyl ion imprinted material and phytic acid silyl ether modification of marine facultative fungi（U（Ⅵ）-ⅡP） two kinds of adsorbent, using infrared spectroscopy, scanning electron microscopy and surface tester test instrument on the adsorbents were characterized, and studied the factors of the two kinds of wastewater treatment of uranium adsorptionperformance, and explore the repeatability and selectivity of the adsorbent, and the the adsorption experiment results were analyzed and the adsorption kinetics and adsorption isotherm model. The main contents are as follows:The first chapter of this thesis to contain a source of uranium wastewater, characteristics, harm and disposal method and phytic acid physicochemical properties and application characteristics were introduced, analysis of chemical modified biological adsorption agent and metal ion imprinted polymer research status, at the same time, the research significance, the main content and innovations are described.Required in the process of the second chapter is a brief introduction to the experimental reagents, instruments and fungal culture and collection process, the adsorbent prepared direction, characterization methods and detailed adsorption experiment method, adsorption kinetic model and the adsorption isotherm model.In the third chapter, by using phytic acid as the modification reagent,of preparing the phytic acid modified fungal PA-ZZF51 biological adsorbent, and by infrared spectroscopy and scanning electron microscopy to change before and after and before and after adsorption by test bacteria were characterized analysis the adsorption mechanism, the results showed that PA-ZZF51 surface becomes rough, binding sites and increased porosity and adsorption of carboxyl, amino, phosphate radical groups are involved in the uranium adsorption process, the adsorption surface smooth and reduce the pore, indicating that phytic acid was successfully grafted to the fungi and participate in the adsorption.Adsorption experiments showed that adsorption agent PA-ZZF51 and unmodified fungi compared and the adsorption effect of U（Ⅵ） increased significantly when the solution pH 5.0, solid-liquid ratio 0.2, reactiontime is 45 min, initial uranium solubility 100 mg g-1 adsorption capacity reached the maximum 4.537 mg g-1, the value is not changed fungal 20.9times. The results of repeated experiments show that the adsorbent PA-ZZF51 has good regeneration performance and can be reused for many times. The desorption rate of HNO3 and HCl is still more than 5.Kinetic study showed that the quasi second order kinetic equations to calculate the theoretical adsorption capacity and actual values close to,linear correlation coefficients are higher than 0.995, indicating that the pseudo second order kinetic model can better describe the adsorption process of uranium PA-ZZF51. At the same time, through the study on isothermal adsorption model found Langmuir isotherm equation of linear regression coefficient 0.9967, shows that the PA-ZZF51 adsorption of uranium accords with Langmuir isothermal adsorption model.The fourth chapter of the fungus powder as matrix, phytic acid as functional monomers, UO22+ as template ion, TEOS as crosslinking agent,the uranium was prepared by sol-gel method（Ⅵ） ion imprinted polymer（U（Ⅵ）-ⅡP）, and the use of infrared spectroscopy, scanning electron microscopy and surface area analysis of U（Ⅵ）-ⅡP were characterized,the results showed that the P=O stretching vibration peaks appeared in the IR spectra, the P-O stretching vibration peak, Si-O-Si symmetric stretching and bending vibration peak, the surface with microsphere dispersed and porous, by adsorption, reduction of porous structure,uniform particle hole is filled, preparation materials（U Ⅵ）-ⅡP compared with NIP, the specific surface area and Kong Rong, but the average pore size, showed that U（Ⅵ）-ⅡP was successfully prepared and the surface of U（Ⅵ） ion specific recognition of imprinted sites corresponding to the enhanced adsorption capacity.In order to scientifically reflect the main factors affecting theadsorption of uranium. Firstly the single factor experiment to explore the solution p H, solid to liquid ratio, reaction time and initial concentration of uranium on uranium adsorption capacity, then reference to the result of single factor experiment, using response surface BBD method is used to optimize the adsorption conditions. The results showed that using single factor method when the solution pH 6, solid-liquid ratio 0.4, reaction time is 60 min, the initial uranium concentration of 50 mg.L-1 when the adsorption capacity reaches the maximum value of 114.44 mg g-1; using the response surface method of BBD when the solution pH 5.79,solid-liquid ratio 0.37, reaction time is 65.25 min, the initial concentration of uranium adsorbed at 52.35 mg. L-1 to achieve the maximum amount of119.805 mg/g, the difference is not of course use, not only considers the effect of single factor on the adsorption of BBD response surface method,and simulated the effects of interaction on the adsorption, and the contour map and 3D response surface can visually see the interactive influence and the maximum adsorption capacity, adsorption condition optimization method that the scientific and reasonable response surface using BBD.The results showed that the desorption rate of EDTA（Ⅵ）-ⅡP was still higher than 90% after 5 cycles, and the results showed that U（Ⅵ）-ⅡP has good stability and can be reused for many times. Selective experiments found that-ⅡP（Ⅵ） Th on（IV） and Cu（Ⅱ） relative selection coefficients were 1.87 and 1.85, respectively, which showed that U（Ⅵ）-ⅡP on U（Ⅵ） has a certain specificity recognition ability, has a good choice of adsorption properties. Kinetic analysis showed that the sorption of U（Ⅵ）-ⅡP is more suitable for described with a pseudo second order kinetics equation, the adsorption rate is controlled by chemical adsorption;at the same time by studying the adsorption isotherm models found that the adsorption process of uranium U（Ⅵ）- ⅡP more accord withLangmuir isothermal adsorption model.In the fifth chapter, the experimental results are summarized in detail, and the future development direction of uranium containing wastewater treatment is also discussed. |
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