摘要
报道了用二环己基18冠6(DC18C6)-正辛醇萃取法从模拟高放废液中去除锶的研究。从高放废液中去除半衰期较长的90Sr,对于高放废液安全处置有着重要意义。系统地研究了DC18C6-正辛醇对Sr2+以及废液中其它阳离子Na+、K+、Cs+、Ni2+、Fe3+、Al3+、Mo(Ⅵ)的萃取性能。结果表明,DC18C6对Sr2+有着良好的萃取选择性,除K+和Mo(Ⅵ)等个别离子外,其它阳离子几乎都不被萃取。在此基础上,建立了用DC18C6-正辛醇从高放浓缩废液中去除锶的工艺流程,并进行了模拟料液的串级实验。经过三级萃取,一级洗涤,四级反萃后,锶的去除率接近99%,产品中锶的重量百分比为76%(原始料液中为0.6%)。该流程具有简单、高去除率、高选择性、适用料液酸度范围较宽等优点,可望用于从我国高放浓缩废液中去除或回收锶。
The removal of strontium from high-level radioactive waste(HLW)by the extraction withdicyclohexano-18-crown-6(DC18C6) in n-octanol has been investigated.The distributioncoefficients of Sr2+and other ions Na+,K+,Cs+,Ni2+,Fe3+,Al3+,Cr3+,and Mo(Ⅵ)inDC18C6-1-octanol-HNO3 were deteimined.The influence of the major cation ions(Na+,Ni2+,Cr3+,Fe3+,Al3+)on the extraction of Sr2+ by DC18C6 in 1-octanol was studied.Theresults show that DC18C6 has a high selectivity of the extraction for Sr. The most cation ions inthe waste solution are not extractable,except for K+and Mo(Ⅵ).A new process for the removalof Sr from acidic high-level radioactive waste was developed and batch countercurrent extractionexperiments with synthetic HLW solution were carried out.Through the process with three ex-traction stages,one scrub stage and four strip stages,99 % of Sr in the feed were removed.Thepercentage in weight of Sr in the products was 76%,while that in the original feed was 0.6%.This process can be used for t he removal or recovery of Sr from HLW.
出处
《核科学与工程》
CSCD
北大核心
1995年第3期259-264,共6页
Nuclear Science and Engineering