冠醚萃取法从高放废液中去除锶─—冠醚萃取锶的化学研究

THE RECOVERY OF STRONTIUM FROM HAW SOLUTION BY CROWN ETHER EXTRACTION─ THE STUDY OF CROWN ETHER EXTRACTION CHEMISTRY

研究了二环己基１８冠６（ＤＣ１８Ｃ６）从硝酸介质中对锶的萃取，选用了正辛醇和第二辛醇作为稀释剂，研究了ＤＣ１８Ｃ６－正辛醇（和第二辛醇）两种萃取体系对锶和硝酸的萃取，同时考察了水相中主要阳离子Ｆｅ３＋、Ａｌ３＋、Ｎａ＋对锶萃取的影响。结果表明，Ｆｅ３＋和Ａｌ３＋对锶的萃取都起着盐析作用，Ｎａ＋在低酸时起盐析作用，而在高酸时起竞争作用。用高放模拟料液进行的实验表明：这两种体系对锶具有较高的萃取能力，并且对其它阳离子有很高的分离系数。反萃实验表明可以用纯水或稀酸从有机相中反萃钢，二次反萃的总反萃率达到９８％以上。根据提出的流程，冠醚萃取法有可能用于从中等酸度（０．５－１．０ｍｏｌ／Ｌ）的高放废液中去除锶。

The extraction behavior of strontium from HAW solution by dicyclohexy1-18-crown-6-1-octanol(or 2-octano1)has been studied. The extraction behavior of strontium and nitric acd,also the influence of the major ontion ions(Fe3+、Al3+、Na+)in aquous phase have been observed.The results show thm the two sation iom Fe3+,Al3+,play a salting-out role in process of ex-tracting strontium but in low mirieacidit is sironger taan in high mitric acid.However, Na+ playsa salting-out tole in low nitgic acid,but a competition role in high nitric acid. The experimentwith synthetie HAW solution showsl both the two systems have high distribution of strontiumand high separation coeffielent.It is easy to strip strontium from organic phase by dilute nitricacid or water The crown ether extraction process can be used in recovery of strontium fromNAW。