Authors:Bao Bo-Rong, Bao Ya-Zhi, Shen Chao-Hong, Wang Gao-Dong, Qian Jun, and Cao Zheng-Bai
A study on solvent extraction of U(VI), Th(IV) and HNO3 from nitric acid media by DEHSO is described. Extraction coefficients of U(VI), Th(IV) and HNO3 as a function of aqueous HNO3 concentration, extractant concentration and temperature have been studied. From the data the compositions of extracted species, equilibrium constants and enthalpies of extraction reaction have been evaluated. Back-extraction of U(VI) and Th(IV) from the organic phase by dilute nitric acid has also been tested. All studies on DEHSO are compared with TBP.
Authors:Shen Chao-Hong, Bao Bo-Rong, Wang Gao-Dong, Qian Jun, Bao Ya-Zhi, and Cao Zheng-Bai
Extraction of uranium(VI), thorium(IV) from nitric acid has been studied with N-octylcaprolactam and N-(2-ethyl)hexylcaprolactam. Distribution coefficients of U(VI), Th(IV) and HNO3 as a function of aqueous NHO3 concentration, extractant concentration and temperature have been studied. The compositions of extracted species, thermodynamic parameters of extraction have been evaluated. Third phase formation in extraction of U(VI) has been studied. Back extraction behavior of U(VI) and Th(IV) from the organic phase has also been tested. The results obtained are compared with those obtained by using TBP under the same experimental conditions.
Authors:Hua Shao, Jing-Tian Han, Guo-Xin Sun, Bo-Rong Bao, Yong-Hui Yang, and Si-Xiu Sun
The extraction performance of uranium(VI) from nitric acid with N-octanoylpiperidine (OPPD) in series of diluents has been investigated. The dependence of extraction distribution on the concentrations of aqueous nitric acid and OPPD and also the temperature has been studied. The experimental results showed that the decreasing order of extraction ability of OPPD is as follows: benzene, dimethyl benzene (DMB), toluene, 1,2-dichloroethene, n-octane, carbon tetrachloride, cyclohexane, chloroform. It cannot be interpreted only on the basis of polarity of the diluents. The interaction between extractant or extracted species and diluent is discussed.
Authors:Han Jing-Tian, Shao Hua, Zhu Jian-Kang, Bao Bo-Rong, Cao Feng-Qi, and Wu Zi-Mei
N-dodecanoylpyrrolidine (DOPOD) was synthesized and used for the extraction of nitric acid and uranyl(VI) ions from nitric
media in toluene. The effects of nitric acid concentration, extractant concentration, temperature, salting-out agent (LiNO3) have been studied. The main adduct of DOPOD and HNO3 is HNO3·DOPOD. The complex formation of uranyl(VI) ion, nitrate ion and DOPOD (UO2(NO3)2·2DOPOD) as extracted species are further confirmed by IR spectra and the values of thermodynamic parameters have also been
Authors:Yang Yan-Zhao, Sun Si-Xiu, Yang Yong-Hui, Zhang Lei, Yu Shao-Ning, and Bao Bo-Rong
The synergic extraction of uranium(VI) from nitric acid solution with petroleum sulfoxides (PSO) and tri-n-butyl phosphate (TBP) mixture has been studied. It has been found that maximum synergic extraction effect occurs if the molar
ratio of PSO to TBP is two to three. The composition of the complex of synergic extraction is UO2(NO3)2·TBP·PSO. The formation constant of the complex isKPT=8.19. The effect of extractant concentration, nitric acid concentration, salting-out agent concentration and temperature
on the extraction equilibrium of uranium(VI) was also studied.