羟基磷灰石的制备及其对铀核素的吸附研究

发布时间：2018-12-31 19:38

【摘要】：本课题制备了纯的及氟掺杂的羟基磷灰石(HA及FHA)粉体和多孔球体环境功能材料,并研究了其对铀(UO22+)的吸附性能。主要研究内容如下:首先,以Ca(NO3)2?4H2O、(NH4)2HPO4和NaF为原料,通过水热法和湿化学沉淀法制备了纳米HA及FHA粉体。水热法制备过程考察了pH、时间、温度及氟含量对HA形貌、晶粒大小、物相和纯度的影响。结果表明,pH=10,温度为140℃,水热时间4h下可合成纳米棒状HA。氟掺杂可使HA的形貌从棒状转化为球状颗粒,结晶性增强;湿化学沉淀法制得HA及FHA样品过程中,考察了氟掺杂对HA的耐酸性及热稳定性影响。结果表明:FHA93和FHA200的耐酸性及热稳定性均优于HA。其次,采用溶胶凝胶和致孔剂相结合的方法制备多孔HA及FHA球体材料。结果表明,石蜡微球用量:HA粉料用量=1:1时,多孔球体的孔洞分布均匀,孔径在100~200μm,抗压强度相对较大。另外抗压强度随着氟掺杂量增加而增强。最后,两种类型的吸附剂(粉体、多孔球体的HA或FHA)对UO22+的吸附性能相当。粉体材料HA、FHA93和FHA200对UO22+的最大吸附量分别为1792mg/g、1752mg/g和1705mg/g;在铀模拟废液pH=4的条件下,多孔球体HA、FHA93和FHA200对UO22+的去除率可分别达到98.5%、98.0%、97.6%。经比较,FHA多孔球体材料更适合应用在工业吸附上。
[Abstract]:In this paper, pure and fluorine-doped hydroxyapatite (HA and FHA) powders and porous spherical environmental functional materials were prepared and their adsorption properties for uranium (UO22) were studied. The main contents are as follows: firstly, Ca (NO3) 2H 2O, (NH4) 2HPO4 and NaF were used as raw materials to prepare nano-HA and FHA powders by hydrothermal method and wet chemical precipitation method. The effects of pH, time, temperature and fluorine content on the morphology, grain size, phase and purity of HA were investigated by hydrothermal method. The results show that nanorods HA. can be synthesized at pH=10, temperature 140 鈩，

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