二苯并-18-冠-6对某些放射性核素的萃取与萃取色层分离

SOLVENT EXTRACTION AND CHROMATOGRAPHIC SEPARATION OF SEVERAL RADIONUCLIDES WITH DIBENZO-18-CROWN-6

摘要: 本文研究了二苯并-18-冠-6对~(22)Na、~(45)Ca、~(86)Rb、~(90)Sr-~(90)Y、~(137)Cs和~(144)Ce等放射性核素的萃取和萃取色层分离。冠醚萃取金属离子具有离子对萃取的特征,据此,选择苦味酸根离子为反离子,以三氯甲烷为溶剂。测定了30℃时Na~+、Rb~+、Cs~+、Ca~(2+)、Sr~(2+)和Ce~(3+)的萃取平衡常数(K_(ex))。对单价和二价金属离子,K_(ex)次序分另0为;Rb~+>Cs~+>Ns~+和Sr~(2+)>Ca~(2+)。使用二苯并-18-冠-6的萃取色层有效地分离了~(22)Na-~(137)Cs、~(45)Ca-~(90)Sr和~(144)Ce-~(90)Sr-~(90)Y。

Abstract: The extraction and chromatographic separation of several radionuclides (22Na, 46Ca, 86Rb, 90Sr-90Y, 137Cs, 144Ce) with dibenzo-18-crown-6 have been investigated. Considering that the extraction of metal ion by the crown ether has the character of ion-pair extraction, the picrate ion was chosen as the counter ion. The solvent was chloroform. The extraction equilibrium constants (Kex) for Na+, Rb% Cs+, Ca2+, Sr2+ and Ce3+ have been determined at 30℃. The Kex sequences of the monovalent and bivalent metal ions are Rb+>Cs + >Na+, Sr2 + >Ca2+ respectively. 22Na-137Cs, 45Ca-90Sr and 144Ce-90Sr-90Y can be effectively separated by extraction chromatography with dibenzo-18-crown-6.