钍-铀燃料后处理中新萃取剂的研究——Ⅲ.N-正辛基己内酰胺萃取铀和钍

RESEARCH ON NEW EXTRACTANTS FOR REPROCESSING OF SPENT Th-U FUEL Ⅲ.EXTRACTION OF URANIUM(Ⅵ) AND THORIUM(Ⅳ) FROM NITRIC ACTD SOLUTION BY N-OCTYLCAPROLACTAM

摘要: 报道了N-正辛基己内酰胺(OCLA)-三甲苯从硝酸介质中萃取铀、钍的实验结果。OCLA对这两种元素的萃取规律类似于TBP,但分配系数(D)比TBP的高。用斜率法求得铀、钍的溶剂化数均为2,硝酸的溶剂化数为1。还对温度对萃取的影响,铀、钍的反萃及三相的形成进行了研究,计算了萃取平衡常数和铀、钍的△H值。

Abstract: Extraction of uranium (Ⅵ), thorium (Ⅳ) and nitric acid has been studied with N-octylcapro-lactam. Distribution coefficients of U(Ⅵ) ,Th(Ⅳ) and HNO3 as a function of aqueous HNO3 concen tration, extractant concentration and temperature have been studied. The compositions of extracted species, thermodynamic parameters of extraction reaction have been evaluated. The third phase formation in the extraction of U(Ⅵ) has been studied. Back extraction behaviours of U(Ⅵ) and Th(Ⅳ) from organic phase have also been tested. The results obtained have compared with those using TBP at the same experimental conditions.