Preparation Of Hydroxyapatite And The Adsorption Behavior Of Uranium On It From Aqueous

In this paper, we prepared hydroxyapatite and fluorine-doped hydroxyapatite(HA and FHA) with powder and porous spherical shape environmental function material, and their sorption properties for uranium(UO22+) have been explored. The main research contents are below:Firstly, we synthesized HA and FHA nanopowders using Ca(NO3)2?4H2O 、(NH4)2HPO4 and Na F as raw materials by the wet chemical precipitation and hydrothermal, respectively. The influences of p H, hydrothermal time, hydrothermal temperature and fluorine-doped content on the powder morphology, particle size, phase and purity of HA have been studied. The results showed that the nanorod HA was synthesized by hydrothermal approach at 140 ℃ for 4h under p H=10. After fluorine-doped, the morphology of HA could gradually changed from the nanorod to the spherical shape, and the crystalline degree of HA increased. We explored the influence of fluorine-doped on the acid corrosion resistance and thermostability of HA during the wet chemical precipitation process. The results exhibited that the acid corrosion resistance and thermostability of FHA93 and FHA200 are better than that of HA.Secondly, we prepared HA and FHA porous spherical material through the combination of sol-gel method and pore foaming agent method. The results showed that when the quality ratio of paraffin microspheres and HA powder was 1:1, the pore size of porous spherical was 100-200μm, the pores were well distributed on the surface of porous sphere HA and the compressive strength was relatively larger. Besides, the compressive strength increases with the fluorine-doped content increasing.Finally, both the powder adsorbent and porous spherical adsorbent exhibited the similar adsorption properties for the removal of UO22+. The maximun UO22+ adsorption capacity of powder HA, FHA93 and FHA200 was 1792mg/g、1752mg/g and 1705mg/g, respectively; When the p H value of the uranium-containing waste water is 4, the UO22+ removal rate of porous spherical HA, FHA93 and FHA200 was 98.5%,98.0% and 97.6% respectively. After comparsion, the FHA porous spherical material is much suitable in the field of industrial application.