Preparation Magnetic U（Ⅵ）ion-imprinted Chitosan Composite Nonomicrosphere For Selective Absorption Of Uranium（Ⅵ）

Imprinted bio-polymer composite magnetic microspHeres has prepared, using theprepared surface imprinting technique imprinted U (VI), combined with the magneticresponse in this paper, which use a natural biopolymer-chitosan as raw materials,and the U（Ⅵ）as a template, to make it not only has the characteristics of proactivelyidentify and fast adsorption, but also has the characteristics of fast magneticseparation under an external magnetic field. And the adsorption performance、identify performance, analytical performance and regeneration performance ofComposite microspHeres to U（Ⅵ）also studied in this paper.The Experimental results revealed that the adsorption rate of0.5g/L imprintedpolymer to uranium about50mg/L can reach89.2%~99.5%while the pH ofuranium solution in the range of2~8,Under the same conditions, the adsorption rateof the solution can reached80.2%only after5min of Polymer adsorption of uranium,it is obvious that the adsorption of the material to uranium solution not only has lessstrict requirements of pH, but also has the fast adsorption rate to uranium; whiledosing the imprinted polymer of1g/L to the uranium-containing solution about500mg/L,the adsorption capacity to uranium can reached172.1mg/g ion capacity hasbeen greatly improved showing that the material has a high uranium adsorptionperformance. it was found that the relative separation factor to the imprinted polymerof uranium, lead ware greater than1, which ware1.15,1.55,1.05respectively,revealthe polymer have a good selective adsorption of uranium in the study of selectiveadsorption to uranium，Proved polymers have a good selective adsorption of uranium.Kinetic studies showed that the adsorption of polymer to uranium conformedpseudo second order kinetic equation, the goodness of fit can reach0.999, whichshows that the material has a high adsorption performance to uranium.It was found that After5times degradation of0.2g/L,25mg/L polymer ads-orption uranium solution in EDTA, microspheres on uranium absorption capacity only reduced by0.08mg/g in the study of imprinted polymer regeneration,which mean thatthe polymer reproducibility is very well,and has good reuse rate.Thermodynamic study show that in the range of laboratory temperature, ΔG~θ<0,which imply that the adsorption of imprinted polymer to uranium is a spontaneousprocess,while ΔH~θ>0, it indicated that the adsorption process is endothermic reaction,elevated adsorption temperature can promote the improvement of the adsorptioncapacity.