(1. 南华大学 化学化工学院,衡阳 421001;
2. 南华大学 湖南省铀尾矿库退役治理工程技术研究中心,衡阳 421001;
3. 南华大学 蛋白质结构与功能重点实验室,衡阳 421001;
4. 南华大学 铀矿冶生物技术国防重点学科实验室,衡阳 421001)
摘 要: 以1,3-二溴丙烷对对叔丁基杯[4]芳烃的下沿进行修饰,再利用 Na2S·9H2O 合成制备一种新型的吸附材料杯[4]芳烃对称硫醚衍生物,并研究其吸附铀的主要影响因素,即U(Ⅵ)溶液pH值、吸附剂投入量、铀初始浓度及反应时间,分析其吸附过程的反应动力学和等温吸附规律。结果表明:当温度为25 ℃时,杯[4]芳烃对称硫醚衍生物吸附铀的最佳条件是pH值为4.0,铀初始浓度为20 mg/ L,杯[4]芳烃对称硫醚衍生物加入量为20 mg以及吸附平衡时间为6 h。杯[4]芳烃对称硫醚衍生物对铀的吸附动力学符合准二级动力学模型,吸附过程为化学吸附,相关系数为0.9998;Langmuir、D-R和 Freundlich 等温线均可较好地拟合吸附过程,说明该吸附体系是一个单层覆盖与多层吸附相结合的模式。红外谱图表明,杯[4]芳烃对称硫醚衍生物吸附一定质量的铀后,在817.82 cm-1和810.10 cm-1处出现了铀酰离子的伸缩振动峰,且未发生主要的结构形态变化。
关键字: 对叔丁基杯[4]芳烃;功能化修饰;吸附行为;铀
(1. School of Chemistry and Chemical Engineering, University of South China, Hengyang 421001, China;
2. Laboratory of Protein Structure and Function, University of South China, Hengyang 421001, China;
3. Hunan Province Engineering Technology Research Center of Uranium Tailings Treatment, University of South China, Hengyang 421001, China;
4. Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China)
Abstract:By modifying the lower edge of tert butyl calix [4] arene with 1,3-dibromopropane, and then utilizing Na2S·9H2O to prepare a new type of absorption material, that is calix [4] arene symmetric sulfide derivatives. The main influence factors of the uranium adsorption, such as pH value of U(Ⅵ) solution, input of adsorbent, initial concentration of uranium and reaction time, were explored, finally the reaction kinetics and adsorption isothermal law of adsorption process were analyzed. The results show that, the best condition of uranium adsorption are as follows: pH value of 4.0, initial concentration of uranium of 20 mg/L, addition adsorbent of 20 mg, adsorption equilibration time of 6 h at 25 ℃. The adsorption kinetics of calix [4] arene symmetric sulfide derivatives to uranium is accorded with pseudo-second order model. The adsorption process which is better fitted by Langmuir, D-R and Freundlich sorption isotherm is chemisorption and its correlation is 0.9998. The adsorption system is a single layer covering combined with multilayer adsorption model. And the infrared spectrum shows that, after adsorbing, a certain quality of uranium by calix [4] arene symmetric sulfide derivatives. In 817.82 cm-1 and 810.10 cm-1, the stretching vibrations of uranyl ion peak appears and the main structure morphology does not change.
Key words: tert butyl calix [4] arene; functional modifying; adsorption behavior; uranium