Advanced Fuel Fabrication Facility, Nuclear Recycles Board, Tarapur, Maharashtra 401502, India; Homi Bhabha National Institute, Anushakti Nagar, Mumbai 400094, India.
Radiochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India.
J Chromatogr A. 2021 Oct 11;1655:462501. doi: 10.1016/j.chroma.2021.462501. Epub 2021 Aug 28.
An extraction chromatography (XC) material containing N,N,N',N'-tetra-n-butyl diglycolamide (TBDGA) and 1-butyl-3-methylimidazolium bis(trifluoromethanesulphonyl) imide (Cmim∙NTf), a room temperature ionic liquid, was used for the uptake of the tetravalent actinide ions Th(IV), Np(IV), and Pu(IV) from nitric acid feed solutions. The uptake of the metal ions followed the trend: Th(IV) < Np(IV) < Pu(IV), which is the same as that of their ionic potential values. While a decrease in the Np(IV) and Pu(IV) uptake was seen with increasing HNO concentration at lower acidities, an opposite trend was observed at higher acidities. Th(IV) uptake was not affected with the acid concentration. In view of the very high uptake and its importance in the nuclear fuel cycle, the major part of the studies was carried out with Pu(IV) ion. The loaded Pu(IV) was back extracted from the XC material using a mixture of 0.5 M oxalic acid and 0.5 M nitric acid. The Pu(IV) uptake by the XC material was fitted into different kinetic and isotherm models. The results conformed to the pseudo-second order kinetic model and the Langmuir monolayer sorption model. Column studies were carried out using a feed having 1.6 mg/L Pu solution in 3 M HNO. While the breakthrough was obtained after passing ca. nine bed volumes, a sharp elution peak was obtained with >99% recovery in about seven bed volumes.
一种含有 N,N,N',N'-四丁基二甘酰胺（TBDGA）和 1-丁基-3-甲基咪唑双（三氟甲烷磺酰基）亚胺（Cmim·NTf）的萃取色谱（XC）材料，室温离子液体，用于从硝酸进料溶液中摄取四价锕系离子 Th(IV)、Np(IV)和 Pu(IV)。金属离子的摄取趋势为：Th(IV)<Np(IV)<Pu(IV)，与它们的离子势值相同。在较低酸度下，随着 HNO3浓度的增加，Np(IV)和 Pu(IV)的摄取量减少，但在较高酸度下则相反。Th(IV)的摄取量不受酸浓度的影响。鉴于 Pu(IV)的摄取量非常高且在核燃料循环中很重要，因此大部分研究都是针对 Pu(IV)离子进行的。使用 0.5 M 草酸和 0.5 M 硝酸的混合物从 XC 材料中反萃负载的 Pu(IV)。XC 材料对 Pu(IV)的摄取符合假二级动力学模型和 Langmuir 单层吸附模型。使用 3 M HNO 中含有 1.6 mg/L Pu 溶液的进料进行柱研究。虽然在通过约九个床体积后获得了穿透，但在约七个床体积内获得了尖锐的洗脱峰，回收率>99%。
