摘要
研究了新型萃取剂N,N'-二乙基-N,N'-二(丙氧基苯基)-2,6-吡啶二酰胺(1a^1c)对铀酰离子(UO2+2)的络合萃取.结果表明,当不加硝酸或硝酸浓度为6 mol/L时,化合物1a对UO2+2的萃取率分别高达99%和94%.在6 mol/L HNO3的高酸度条件下,化合物1a能实现UO2+2和镧系元素(La,Eu及Yb)的选择性分离[分离比SFU(Ⅵ)/Ln(Ⅲ)>20];而化合物1b和1c则可以实现UO2+2和轻镧系元素(La,Eu)之间的分离.双对数图(lg-lg plot)实验结果表明,化合物1a^1c与UO2+2的萃合比在1~2之间,表明同时存在2∶1和1∶1两种比例的萃合物.核磁共振波谱和红外光谱数据证明吡啶氮和羰基氧参与了对UO2+2的配位.
To acquire a more efficent and selective dipicolinamide,the affinity of three novel diamide derivatives of dipicolinic acids N,N＇-diethyl-N,N＇-bis（ propoxyphenyl）-2,6-dipicolinamide（ 1a—1c） for uranyl ion was investigated by liquid-liquid extraction method. In the absence of HNO3 and in the presence of 6 mol / L HNO3,the extractability of compound 1a for uranyl ion was 99% and 94%,respectively. At the same high acidity,selective separation of uranyl from lanthanides（ La,Eu and Yb） was achieved using compound 1a as extractant [SFU（ VI） / Ln（ III）〉20]. In contrast,compounds 1b and 1c were able to separate uranyl ion from lighter lanthanides（ La and Eu）. Result of lg-lg plot experiments indicated the stoichiometric ratios of compounds 1a,1b and 1c with uranyl were found to fall between 1 and 2,suggesting the presence of two kinds of extracted species in 2 ∶ 1 and 1 ∶ 1 ratios（ extractant ∶ uranyl）.^1H NMR and FTIR spectra of the extracted complexes implicated the involvement of nitrogen atom in the pyridine ring and carbonyl group in coordinating uranyl ion.The results showed that compound 1a is the most promising extractant and probably can be used in the recycling of uranyl ion.
出处
《高等学校化学学报》
SCIE
EI
CAS
CSCD
北大核心
2015年第8期1485-1490,共6页
Chemical Journal of Chinese Universities
基金
国家自然科学基金(批准号:21471105)
国家自然科学基金国家基础科学人才培养基金(批准号:J1210004,J1103315)资助~~
