Actinide Partitioning From HLW in a Continuous Didpa Extraction Process by Means of Centrifugal Extractors

Studies on uranium(VI) pertraction across a N,N,N′N′-tetraoctyldiglycolamide (TODGA) supported liquid membrane

“…N,N,N ,N -tetraoctyldiglycolamide (TODGA, Fig. 1 [2,3]) appears to be one of the most promising 'green' extractants for trivalent actinide ions and has shown improved performance as compared to carbamoylmethylphosphine oxide (CMPO) [4], tri-n-alkyl phosphine oxide (TRPO) [5] and di-iso-decyl phosphoric acid (DIDPA) [6]. However, though other extractants preferentially extract the hexa-and tetravalent actinide ions as compared to the trivalent ions, TODGA is unique where trivalent actinides are preferentially extracted over other oxidation state ions [7].…”

Challenges for Actinide Separations in Advanced Nuclear Fuel Cycles

“…Tachimori and coworkers (13,14) investigated the possibility of replacing HDEHP with DIDPA. The results showed that DIDPA was able to extract americium and neodymium at a higher acidity than HDEHP, but with a decrease in separation factor between the two elements.…”

“…In the partitioning program developed in China, monofunctional trialkylphosphine oxide extractants, TRPO (10,11), have been employed in conjunction with a necessary denitration step. An/Ln co-extraction can also be accomplished using a cation exchanging extractant such as bis(2-ethylhexyl) phosphoric acid, HDEHP (12) or di(isodecyl) phosphoric acid, DIDPA (13,14). As is true for the TRPO process, cation exchangers can only be used after the acidity of the feed is reduced below that of dissolved spent fuel.…”

Carrier Facilitated Transport of Europium(III) Across Supported Liquid Membranes ContainingN,N,N′,N′-tetra-2-ethylhexyl-3-oxapentane-diamide (T2EHDGA) as the Extractant

“…This strategy, known as ''Actinide Partitioning'', is one of the challenging areas of research in the back end of the nuclear fuel cycle and requires selective reagents for the partitioning of minor actinides, especially the trivalent actinides (1,2). Several extractants such as tri-alkyl phosphine oxide (TRPO), carbamoyl methyl phoshphine oxides (CMPO), di-iso-decylphosphoric acid (DIDPA), malonamides such as N,N 0 -dimethyl-N,N 0 -dibutyl tetradecyl malonamide (DMDBTDMA), and diglycolamides (DGA) have been evaluated for the extraction of trivalent actinides under HLW conditions (3)(4)(5)(6)(7)(8)(9). Out of these, the DGA extractants have been found to be most promising due to large extraction coefficients with the trivalent actinides and their ''green'' nature which leads to much lower secondary waste volumes as compared to the phosphorous based extractants such as CMPO and TRPO (3).…”