Derivatives of imidopyrophosphoric acids as extractants. Part 6. Determination of metal ion extraction mechanism of N,N-N[prime],N[prime]-octabutylimido-diphosphotetramide by potentiometry

Journal Article · Tue Mar 01 00:00:00 EST 1994 · Solvent Extraction and Ion Exchange; (United States)

DOI:https://doi.org/10.1080/07366299408918217· OSTI ID:7114404

Jarvis, N V ^[1]; Krueger, L; Preez, J G.H. du ^[2]

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1. Atomic Energy Corporation of South Africa, Ltd., Pretoria (South Africa)
2. Univ. of Port Elizabeth (South Africa)

Extraction of tri-, tetra- and hexavalent metal ions by N,N-N[prime],N[prime]-octabutylimidodiphosphotetramide has been investigated. Imidodiphosphoryl extractants show promise for treatment of nuclear waste but the optimum extractant structure must still be determined. Extraction of rare earths was investigated using two-phase potentiometric titrations as the more conventional slope analysis techniques could not be applied. The data thus obtained were analysed by the ESTA library of programs which was designed for modelling solution equilibria in aqueous phases. Results obtained showed that ESTA may be used for modelling two-phase systems providing corrections are made. Models were obtained for the extraction of Nd(III), Eu(III), Y(III) and Yb(III). Extraction equilibrium constants could be calculated as well as distribution ratios showing that imidodiphosphoryl extractants are promising as rare earth extractants. Extraction mechanisms were complicated with a number of species being formed proving that traditional slope analysis techniques for mechanistic determination would not have been successful here. 2 refs., 9 figs., 3 tabs.

• OSTI ID: 7114404
• Journal Information: Solvent Extraction and Ion Exchange; (United States), Vol. 12:2; ISSN 0736-6299
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
EUROPIUM COMPOUNDS
SOLVENT EXTRACTION
NEODYMIUM COMPOUNDS
RARE EARTH COMPOUNDS
EQUILIBRIUM
MATHEMATICAL MODELS
YTTERBIUM COMPOUNDS
YTTRIUM COMPOUNDS
AMIDES
COMPILED DATA
COMPUTER CODES
DISTRIBUTION
POTENTIOMETRY
RADIOACTIVE WASTE PROCESSING
SOLVENTS
DATA
EXTRACTION
INFORMATION
MANAGEMENT
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
PROCESSING
RADIOACTIVE WASTE MANAGEMENT
SEPARATION PROCESSES
TITRATION
TRANSITION ELEMENT COMPOUNDS
WASTE MANAGEMENT
WASTE PROCESSING
400105* - Separation Procedures
052001 - Nuclear Fuels- Waste Processing