Separation of neptunium (IV) from actinides by solid phase extraction using a resin containing Aliquat 336

Highly efficient uptake of neptunium from acidic feeds using two solid phase extraction resins containing diglycolamide-functionalized calix[4]arene ligands

“…As mentioned in a separate section below, other actinide ions such as Am 3 + and Pu 4 + , and UO 2 2 + to a much lesser extent, were also extracted by the resins suggesting that the resins can be used for the separation of actinide ions from acidic radioactive waste solutions. Table 2 lists the uptake data for Np(IV) with the two SPERs along with other analogous resins reported in the literature [23][24][25][26][27] . As almost no data are available of DGA-based resins such as TODGA for the uptake of Np(IV) ions, a comparison is made with Th(IV) and Pu(IV) data.…”

Carrier mediated transport of actinides using hexa–n-hexylnitrilotriacetamide (HHNTA)

“…Sodium carbonate was used to strip U(VI) as it forms a very strong UO 2 (CO 3 ) 3 4− complex [31]. For tetra-valent actinide ions, a mixture of 0.5 M oxalic acid and 0.5 M HNO 3 was reported to be quite efficient [32].…”

Extraction of Np(IV/VI) from nitric acid medium using three different tripodal diglycolamide ligands in ionic liquid: Batch extraction, spectroscopic and electrochemical investigations

“…Neptunium is one of the very significant minor actinide elements and is of real concern during the high-level liquid waste (HLLW) management [1,2]. This is since 237 Np, the major constituent of the total Np produced in the nuclear reactors, has a significantly long half-life (t 1/2 : 2.1 Â 10 6 y) making the radioactive waste processing quite complicated [2][3][4][5]. In view of this, its separation is of paramount importance as it can significantly reduce the cost of surveillance of the vitrified waste blocks containing the waste oxide [2,4].…”

“…This is since 237 Np, the major constituent of the total Np produced in the nuclear reactors, has a significantly long half-life (t 1/2 : 2.1 Â 10 6 y) making the radioactive waste processing quite complicated [2][3][4][5]. In view of this, its separation is of paramount importance as it can significantly reduce the cost of surveillance of the vitrified waste blocks containing the waste oxide [2,4]. Furthermore, the recovered 237 Np can find many applications including that of 238 Pu production for use as pacemakers or as power sources [6].…”

“…In a subsequent development, multiple-DGA ligands were found to be significantly more promising than the commonly employed simple DGA ligands such as TODGA (N,N,N',N'-tetra-n-octyl diglycolamide). Though there are several classes of multiple-DGA ligands such as those anchored onto calix [4]arene [21,25,26], pillar [5]arene [27] and dendritic [24,28,29] scaffolds, the tripodals have been really interesting as they can afford nine donor atoms from the six amidic and three etheric 'O' atoms, which can easily satisfy the coordination numbers of the trivalent / tetravalent actinide ions. We have employed several multiple DGA ligands for the extraction of Np from acidic feed solutions [21,22,24,28,30,31] out of which the tripodal DGA ligands (Fig.…”