Halogen protected cobalt bis(dicarbollide) ions with covalently bonded CMPO functions as anionic extractants for trivalent lanthanide/actinide partitioning
详细信息查看全文 | 推荐本文 |
摘要
Halogen protected CMPO derivatives of the cobalt bis(dicarbollide) ion (1鈭?/sup>) were synthesized with the aim to develop efficient extraction agents with increased stability for liquid-liquid extraction of lanthanides and actinides from high-level activity nuclear waste. New halogen protected compounds of the general formulation [3,3鈥?Co(III)-(8-CMPO-(CH2-CH2O)2-1,2-C2B9H10)(8鈥?X-1鈥?2鈥?C2B9H10)]鈭?/sup> (where X = Cl, Br, I; CMPO = Ph2P(O)-CH2C(O)(t-C8H17)N-) (4a-c), were prepared and studied for Ln(III)/An(III) group extraction. These compounds were accessible via halogenated zwitterionic amino derivatives [3,3鈥?Co(III)-(8-t-C8H17NH2-(CH2-CH2O)2-1,2-C2B9H10)(8鈥?X-1鈥?2鈥?C2B9H10)] (3a-c), prepared by several different synthetic methods. All the compounds were characterized by a combination of 11B NMR, 1H high field NMR, ESI-MS, HPLC and other methods. The effect of the halogen in the structures of 4a-c on the extraction properties is outlined. In general, these compounds preserve good extraction efficiency and exhibit a better stability. On the other hand, the character of the halogenated ion 1鈭?/sup> seems to prevail in these compounds and their best extraction efficiency was achieved in more polar auxiliary solvents such as nitro-, chloro-solvents or a laurylonitrile-dodecane mixture than in mixtures of hexyl methyl ketone (HMK) and dodecane (D) applied as the optimum solution for extraction with the parent compound 4, which contains no halogen in the structure. The reason for this behaviour can be seen in the substitution of the polarized B(8鈥?-H鈭?/sup> bond, which may contribute to complexation or protonation at the B(8)-O-site, smoothing thus the solubility of 4 in low polar solvents.

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700