摘要
为了达到从稀土浸出液中富集回收稀土的目的,研究了LEWATIT TP 207树脂对硫酸盐介质中La(Ⅲ)的吸附性能及机制。通过静态吸附实验,考察了反应时间、La(Ⅲ)初始浓度、p H值等因素对树脂吸附性能的影响;并对树脂吸附La(Ⅲ)的动力学和热力学特性进行了研究。结果表明:p H值为4.00是硫酸盐介质中La(Ⅲ)的较优吸附条件,树脂的静态饱和吸附容量为121.93 mg·g^(-1)。吸附过程遵循Langmuir吸附等温方程,其相关系数为1.00。准一级吸附动力学模型能够很好地拟合LEWATIT TP 207树脂吸附La(Ⅲ)的过程,当La(Ⅲ)初始浓度为10 mmol·L^(-1)时,其相关系数为0.98。热力学参数表明:在293 K时吸附过程可自发进行,且是一个吸热、熵增的过程(ΔH=5.00k J·mol^(-1),ΔS=23.75 J·mol^(-1)·K^(-1),ΔG_(293)=-1.96 k J·mol^(-1))。红外光谱分析表明:树脂吸附La(Ⅲ)的过程为化学吸附,树脂功能基中C=O的O原子以及氨基中的N原子均与La^(3+)发生配位反应。
In order to enrich and recover rare earth from rare earth leaching solution, the adsorption properties and mechanism of La （Ⅲ） on LEWATIT TP 207 chelating resin in sulfate medium were studied. The effect of contact time, initial concentration of La （Ⅲ） and initial pH value was investigated by batch method, and the kinetic and thermodynamic characteristics of resin adsorption on La （Ⅲ） were investigated. The results showed that pH = 4.00 was the optimum adsorption conditions in sulfate medium and the static saturated adsorption capacity of the resin was 121.93 mg.g-l The adsorption process follows the Langmuir adsorption isotherm equation with a correlation coeffi- cient of 1.00. The pseudo first order adsorption kinetics model can well fit the adsorption process of I.a （Ⅲ） onto LE- WATIT TP 207 resin, when the initial concentration of La （Ⅲ） is 10 mmol ·L-1, and the correlation coefficient is 0. 98. Thermodynamic parameters such as standard enthalpy （△H = 5.00 kJ.mol - 1 ）, entropy （ △S = 23.75 J·mol-1·K- 1 ） and free energy （△G293 =-1.96 kJ·mo1-1） indicated that in the 293 K adsorption process is a spontaneous endo- thermic and entropy increment process. IR spectra indicated that the adsorption of La（Ⅲ） by the resin was chemi- cal adsorption, the oxygen atom of C = O and the nitrogen atom of the amino group in the functional group of the resin were reacted with La3＋.
作者
徐海波
周洁英
王超
李开中
杨幼明
Xu Haibo;Zhou Jieying;Wang Chao;Li Kaizhong;Yang Youming(School of Metallurgy and Chem-ical Engineering,Jiangxi University of Science and Technology,Ganzhou 341000,China)
出处
《中国稀土学报》
CAS
CSCD
北大核心
2018年第5期593-601,共9页
Journal of the Chinese Society of Rare Earths
基金
国家自然科学基金项目(5177041221)资助
