Bidentate neutral organophosphorus

Diphcnyl-/V,/V-di obutylcarbamoylmcthylphosphinc oxide (Ph2-CMPO, Figure 3.3), a bidentate neutral organophosphorus compound (BNOPC) derived from the TRUEX process, which proved to be efficient for the removal of actinides and REEs. 

FIGURE 3.6 Bidentate neutral organophosphorus compounds (BNOPCs) diphosphine dioxides. 

Smirnov I.V. Anomalous effects in extraction of lanthanides and actinides with bidentate neutral organophosphorus extractants. Role of proton hydrate solvates. Radiochemistry (2007), 49 (1), 44-54. 

It is well-known that certain bidentate neutral organophosphorus compounds are far better extractants than their monodentate analogues (1, ). 

Bidentate neutral organophosphorus compounds were synthesized in the laboratory of organophosphorus compounds, USSR Academy of Sciences as described in ( -11), the tri- and tetradentate compounds as described in (11). The reagents were dissolved in chloroform or cTTchloroethane. 

Turanov, A.N. Karndashev, V.K Baulin, V.E. (2008). Effect of Ionic Liquids on the Extraction of Rare-earth Elements by Bidentate Neutral Organophosphorus Compounds from Chloride Solutions. Russ.. Inorg. Chem., Vol.53, pp. 970-975... 

Bidentate phosphate compounds. The organophosphorus bidentate extractants are neutral species extractants that undergo no keto-enolization and have no exchangeable hydrogens (as is the case in extraction by the bidentate diketones). They contain either two P=0 groups or one P=0 and one C=0 group. The carbamoylmethyl-phosphonates (CMPs) and carbamoylphosphonates (CPs) are examples of the latter, while the tetraalkyldiphosphonates and tetraalkyl-diphosphinedioxides [or bis-(disubstituted phosphinyl)-alkanes] are examples of the former. 

Since TBP leaves Am(iii) behind in an addic raffinate, an effective extractant is needed to remove Am(iii) from such media. Siddall found that bidentate extractants have this desirable property [44]. Schulz [45] and Mclsaac [46] at the Hanford and Idaho Falls sites, respectively, have recently revived interest in plant-scale application of neutral bidentate organophosphorus extractants, particularly dihexyl-iV,iV-diethylcarbamoyl methylenephosphonate (DHDECMP) and dibutyl-iV,iV-diethylcarbamoyl methylenephosphonate (DBDECMP). The binding of actinide ions to DHDECMP has not been eluddated fully. Horwitz [335] states that in perchloric add the extractant is... 

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