摘要
初步研究了取代基对二烷基二硫代膦酸分离三价镧系和锕系元素的影响。分别以取代基为正辛基、1 甲基庚基、2 乙基己基、2 ,4 ,4 三甲基戊基的 4种二烷基二硫代膦酸为萃取剂 ,煤油为稀释剂 ,测定水相酸度、萃取剂浓度对几种萃取剂萃取示踪量Am(Ⅲ )和Eu(Ⅲ )的影响。结果表明 :除二正辛基二硫代膦酸萃取示踪量Eu(Ⅲ )外 ,以lgD对 pH作图得到斜率接近 3的直线 ,以lgD对lgc( (HA) 2 )作图得到斜率接近 2的直线。取代基为正辛基、1 甲基庚基、2 乙基己基、2 ,4 ,4 三甲基戊基的 4种二烷基二硫代膦酸萃取示踪量Am(Ⅲ )的 pH1/2 分别为 2 31、2 56、2 58、3 14;取代基为 1 甲基庚基、2 乙基己基、2 ,4 ,4 三甲基戊基的 3种二烷基二硫代膦酸萃取示踪量Eu(Ⅲ )的pH1/2 分别为 3 95、4 0 1、4 4 2。取代基对二烷基二硫代膦酸萃取Am(Ⅲ )和Eu(Ⅲ )的能力有明显影响 ,萃取能力按取代基为正辛基、1 甲基庚基、2 乙基己基、2 ,4 ,4 三甲基戊基的顺序依次减小 ,与几种萃取剂的酸性电离常数大小趋势相同 ,但它们萃取分离示踪量Am (Ⅲ )和Eu(Ⅲ )
The effect of alkyl group structure of dialkyldithiophosphinic acid on separating Am(Ⅲ) from Eu(Ⅲ) is investigated. With four kinds of dialkyldithiophosphinic acids(HA) with different alkyl group of C 8(alkyl= n octyl, 1 methylheptyl,2 ethylhexyl,2,4,4 trimethylpentyl) as extractants and kerosene as diluent, the dependencies of extracting Am(Ⅲ) and Eu(Ⅲ) on pH and extractant concentration are determined. The slopes of lg D ～pH dependencies are close to 3 and the slopes of (lg D -3pH)～lg c ((HA) 2) are close to 2 except for di n octyldithiophosphinic acid extracting Eu(Ⅲ) . While the organic phases are 0.2 mol/L extractants in kerosene and aqueous phase is 1 mol/L NaNO 3, the pH 1/2 values of aqueous phase for extracting tracer amount of 241 Am by HA with R= n octyl, 1 methylheptyl, 2 ethylhexyl, 2,4,4 trimethylpentyl are 2 31, 2 56 ,2,58, 3 14 , respectively, and the pH 1/2 values of aqueous phase for extracting tracer amount of 152,154 Eu(Ⅲ) by HA with R=1 methylheptyl, 2 ethylhexyl, 2,4,4 trimethylpentyl are 3 95,4 01 ,4 42, respectively. The alkyl group has some effect on the extraction power to Am(Ⅲ) and Eu(Ⅲ), but has no substantial effect on SF Am/Eu .
出处
《原子能科学技术》
EI
CAS
CSCD
2001年第B05期76-82,共7页
Atomic Energy Science and Technology
