取代酰胺萃取稀土元素的研究

Solvent Extraction of Lanthanoid with Substituted Amides

本文研究了ＮＮ二甲庚基乙酰胺（Ｎ５０３）、ＮＮ二正混合基乙酰胺（Ａ１０１）和Ｎ苯基Ｎ辛基乙酰胺（Ａ４０４）三种取代酰胺对稀土元素的萃取行为．结果表明：取代酰胺在高酸浓度介质中对稀土几乎不萃取；在中性偏酸性介质中，选择有效半径较大的苦味酸根（Ｐｉｃ－）作为伴随阴离子，对稀土元素有较大的萃取率；稀释剂的介电常数大小对萃取能力有一定的影响．综合考虑取代基的诱导效应和空间效应对酰胺官能团的影响，其配位能力Ｎ５０３＞Ａ１０１＞Ａ４０４．

The solvent extraction behavior of lanthanoid with three kinds of substituted amide have been investigated. The substituted amides are N 503 ,A 101 ,A 404 .The results show that: substituted amides do not extract lanthanoid ions in strong acid medium, but do very well in pH=5.0～6.0. Accompaning anions and dituents directly influence extraction rate of lanthanoid ion. The inductive effect and space effect of substituents also influence the coordinate ability, i. e. N 503 >A 101 >A 404 .The composition of extracting compounds is RE·B 3·(Pic -]) 2]·Cl.