含铀废水处理对环境保护和人类健康具有重要意义。吸附法是处理含铀废水的重要方法，但高效、稳定的吸附材料研发仍然面临挑战。羟基磷灰石（HAP）对铀具有较高的亲和力，但用于含铀废水处理，存在吸附量低、稳定性差及固液分离难等不足。本论文探讨了多种HAP的改性方法，制备了模板介导合成（T-HAP）、元素掺杂（D-HAP）、氧化石墨烯增强（G-HAP）、磁改性（M-HAP）等系列羟基磷灰石改性材料，研究了改性HAP材料吸附铀的特性，探讨了相关影响因素及吸附机理，为含铀废水处理提供了有价值的吸附材料。本论文取得的主要成果如下：（1）发现模板介导合成、元素掺杂、氧化石墨烯增强均能明显改善HAP材料的形态和孔隙结构、提升铀吸附量。与HAP相比，T-HAP、D-HAP、G-HAP等改性HAP复合材料的最大铀吸附量分别提升了23.45%、35.18%、27.76%，最大理论吸附量达1528.16、1426.53、1635.28 mg/g。利用铁掺杂、共沉淀，结合水热法，成功合成了具有较好磁分离性能的磁性羟基磷灰石，解决了HAP分离效果不佳的难题；添加双模板剂后，M-HAP复合材料的饱和磁化强度提升了51.52%。（2）阐明了改性羟基磷灰石材料吸附铀的特性及吸附动力学、等温线和热力学规律。初始pH、吸附剂用量均会明显影响铀吸附，在pH=3.5、吸附剂用量为50 mg/L时，铀吸附量最大。发现改性HAP材料吸附动力学数据均符合拟二级动力学模型，主要为化学吸附过程；发现Langmuir模型能更好地拟合T-HAP材料吸附等温线数据，Sips模型能更好地拟合D-HAP、G-HAP、M-HAP材料吸附等温线数据。随温度升高，改性HAP材料对铀的吸附量增加，热力学计算结果表明为熵增、吸热过程。阳离子K+、Ca2+、Mg2+ 对铀吸附影响较小，Na+ 有一定的影响，Al3+、Fe3+ 影响较大；阴离子PO43-、SO42-、ClO4- 对铀吸附影响较小，Cl-、NO3- 有一定影响，CO32- 影响较大。（3）揭示了改性羟基磷灰石材料吸附铀离子的作用机理，包括配位络合、静电作用、离子交换和溶解-沉淀。分析了改性HAP材料吸附铀前后的FT-IR光谱、XPS能谱、XRD图谱变化，阐明了U(Ⅵ)离子通过多种相互作用协同吸附，羟基和磷酸基团在铀吸附中发挥重要作用，形成的固相矿物晶体结构与钙铀云母、氢铀云母、磷酸铀酰氢具有一致性，揭示了羟基磷灰石吸附铀的化学反应过程。

The treatment of uranium-containing wastewater is essential for protecting the environment and human health. Adsorption is an important method to treat uranium-containing wastewater, but the development of efficient and stable adsorption materials is still facing challenges. Hydroxyapatite (HAP) has a high affinity for uranium. However, it has some shortcomings, such as low adsorption capacity, poor stability and difficult separation of solid and liquid when used to treat uranium-containing wastewater. In this paper, a variety of HAP modification methods were discussed, and a series of HAP- modified materials such as template-mediated synthesis (T-HAP), element doping (D-HAP), graphene oxide enhanced (G-HAP) and magnetic modification (M-HAP) were prepared. The adsorption properties of modified HAP materials for uranium were studied, and the related influencing factors and adsorption mechanisms were discussed. It provides a valuable adsorbent for treating uranium-containing wastewater. The main achievements of this paper are as follows:(1) It was found that template-mediated synthesis, element doping and graphene oxide enhancement can significantly improve the morphology and pore structure of HAP materials and increase the adsorption capacity of uranium. Compared with HAP, the maximum uranium adsorption capacity of T-HAP, D-HAP and G-HAP composites increased by 23.45%, 35.18% and 27.76%, respectively, and the maximum theoretical adsorption capacity reached 1528.16, 1426.53 and 1635.28 mg/g, respectively. The magnetic hydroxyapatite with good magnetic separation performance was successfully synthesized by iron doping, co-precipitation and hydrothermal method, which solved the problem of poor separation effect for HAP. The saturation magnetization of M-HAP composites increased by 51.52% after the addition of double-template agents.(2) The adsorption properties, kinetics, isotherm and thermodynamics of uranium by modified HAP material were expounded. Both the initial pH and the amount of adsorbent can significantly affect the adsorption of uranium. When pH=3.5 and the amount of adsorbent was 50 mg/L, the adsorption amount of uranium was the largest. It was found that the adsorption kinetics data of modified HAP materials were consistent with the pseudo-second-order kinetic model, showing that it was mainly a chemical adsorption process. The Langmuir model can better fit the adsorption isotherm data of T-HAP material, and the Sips model can better fit the adsorption isotherm data of D-HAP, G-HAP and M-HAP material. The adsorption capacity of modified HAP materials on uranium increased with the increase in temperature, and the thermodynamic calculation results showed that it was a process of entropy increase and heat absorption. Cations K+, Ca2+ and Mg2+ had minimal effects on uranium adsorption, Na+ had some effects, and Al3+ and Fe3+ had a more significant effect. Among anions, PO43-, SO42- and ClO4- had minimal effects on uranium adsorption, Cl- and NO3- have some effects, and CO32- had a more significant effect. (3) The adsorption mechanism of uranium ions by modified HAP materials was revealed, including coordination complexation, electrostatic interaction, ion exchange and solution-precipitation. The changes in FT-IR spectra, XPS spectra and XRD patterns before and after uranium adsorption by modified HAP materials were analyzed. It was demonstrated that U(Ⅵ) ions were synergically adsorbed through various interactions, and hydroxyl and phosphate groups played an essential role in the uranium adsorption. The crystal structure of the formed solid phase mineral was consistent with that of metaautunite-9A, chernikovite and hydrogen uranyl phosphate, respectively. The chemical reaction process of uranium adsorption by hydroxyapatite was revealed.