磺酰基桥连杯[4]芳烃萃取分离钍与稀土  

Extraction and Separation of Thorium and Rare Earths with p-tert-butylsulfonylcalix[4] Arene

作　　者：孙玉丽[1,2] 尚庆坤[1] 王小飞 卢有彩[2] 张志峰[2] 廖伍平[2] 

机构地区：[1]东北师范大学化学学院,吉林长春130024 [2]中国科学院长春应用化学研究所,稀土资源利用国家重点实验室,稀土及钍清洁分离工程技术中心,吉林长春130022

出　　处：《中国稀土学报》2013年第5期582-587,共6页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金(51074148;51222404和91026024);973项目(2012CBA01206)资助

摘　　要：为筛选出特效的钍萃取剂,研究了对叔丁基磺酰基桥连杯[4]芳烃(H4L)在盐酸介质中对钍和稀土的萃取。实验结果表明,在0.75<pH<2时,钍的萃取率随酸度降低迅速升高,而稀土离子(La,Eu,Yb,Y)的萃取几乎不受影响,都保持在20%以下,因而对叔丁基磺酰基桥连杯[4]芳烃对钍和稀土表现出良好的分离能力。采用斜率法研究了H4L萃取钍的机制,结果表明钍被以Th(H2L)·Cl2和Th(H2L)2的1∶1混合物的形式萃入有机相,萃取反应的平衡常数为102.14,热力学常数ΔH,ΔG和ΔS分别为15.13 kJ·mol-1,12.21 kJ·mol-1和9.79J·(mol·K)-1。反萃实验表明,该萃取体系可在较低的酸度下实现钍的反萃。In order to find a good thorium extractant, the extraction and separation of thorium and rare earths by p-tert-butylsulfonylcalix [ 4 ] arene （ abbrevia- ted as H4L） were studied in hydrochloric acid medi- urn. The thorium extraction increased markedly with the increasing equilibrium pH in the range from 0.75 to 2, while the low extraction of rare earths kept nearly unchanged. So H4L is a good extractant for the sepa- ration of thorium and rare earths. Thermodynamic study on the thorium extraction indicated that thorium was extracted into the organic phase by a 1：1 mixture of Th （ H2 L）- C1z and Th （ H2 L） 2 with the logarithm of the equilibrium constant being of 2. 14. Thermody- namic functions, AH, AG and AS, were calculated to be 15.13 kJ.mol-1, 12. 21 kJ-mol-X and 9. 79 J-（mol.K） -1, respectively. Furthermore, the loaded organic phase could be stripped easily.

关 键 词：溶剂萃取 杯芳烃 钍 稀土 

分 类 号：O658.2[理学—分析化学]