张莉莉,许成,陈元涛,张炜.MIL-125(Ti)/NH2-MIL-125(Ti)材料的制备及其对铀酰离子吸附性能的研究[J].环境科学学报,2020,40(6):2055-2065
MIL-125(Ti)/NH2-MIL-125(Ti)材料的制备及其对铀酰离子吸附性能的研究
- Preparation of MIL-125(Ti)/NH2-MIL-125(Ti) materials and their adsorption properties for uranyl ions
- 基金项目：国家自然科学基金（No.21667024）
- 张莉莉
- 青海师范大学化学化工学院, 西宁 810008
- 许成
- 青海师范大学化学化工学院, 西宁 810008
- 陈元涛
- 青海师范大学化学化工学院, 西宁 810008
- 张炜
- 青海师范大学化学化工学院, 西宁 810008
- 摘要：寻找具有高效、高吸附量、高选择性的吸附剂处理放射性的含铀废水，对环境保护具有现实意义.通过溶剂热法合成两种金属有机框架材料MIL-125和NH2-MIL-125，并用X-射线衍射仪（XRD）、扫描电镜（SEM）、傅里叶变换红外光谱仪（FT-IR）、热重分析仪（TGA/DSC）等仪器对两种材料的结构和形貌分别进行表征，探究不同的初始pH、初始铀浓度、吸附时间等条件下两种材料分别对UO22+吸附性能的影响.结果表明：本实验成功合成了MIL-125和NH2-MIL-125两种材料；当初始pH分别为5和8时，MIL-125和NH2-MIL-125材料对UO22+的吸附效果最好.通过Langmuir和Freundlich方程进行热力学拟合可知，两种材料的吸附过程更符合Langmuir方程，在25℃时MIL-125、NH2-MIL-125对UO22+的最大吸附量分别为264.4 mg·g-1和327.3 mg·g-1，最佳吸附时间分别为480 min和70 min.
- Abstract：It has realistic significance to environmental protection, finding the efficient, high-absorption and high-selectivity adsorbents to deal with uranium-containing wastewater. Herein we report two Mental-Organic Framework materials MIL-125 and NH2-MIL-125 synthesized by solvothermal method. The materials have been characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR) and thermogravimetry analysis/differential scanning calorimetry (TGA/DSC). The adsorption performance of the adsorbents for UO22+ were investigated at different initial pH, uranium concentration, and contact time. The results showed that MIL-125 and NH2-MIL-125 were synthesized successfully, and the synthesized powders exhibited the strongest adsorption capacity for UO22+ when the initial pH was 5 and 8, respectively. A comparison of the Langmuir, Freundlich equations to describe UO22+ adsorption properties of the two materials showed that the adsorption processes were more consistent with the Langmuir equation. At 25℃, the maximum adsorption capacity of MIL-125 and NH2-MIL-125 were 264.4 mg·g-1 and 327.3 mg·g-1, and the optimal adsorption time were 480 min and 70 min.
