Thermodynamics of the extraction of Eu(III) and Am(III) with synergistic mixtures of thenoyltrifluoroacetone and a linear polyether

Conference · Sat Jan 01 04:00:00 EST 1983

OSTI ID:5919871

Ensor, D D; Shah, A H

The extractions of trivalent lanthanides and actinides by synergistic mixtures of thenoyltrifluoroacetone (HTTA) and a variety of neutral oxygen donors are well documented. The large increase in the extent of extraction of the metal ion into the organic phase is believed to occur by one of three possible mechanisms. The first involves the direct replacement of residual waters of hydration on the metal by the neutral donor. In the second proposed mechanism, the residual waters remain attached to the metal and the neutral oxygen donor hydrogen bond to the complex through the waters. The final mechanism assumes the complex is not hydrated and the addition of the neutral donor requires the metal to increase its coordination number. A recent review of the synergistic effect showed that the proper interpretation of the mechanism requires the measurement of ..delta..H and ..delta..S for the reaction. The synergistic capabilities of a linear polyether, 1,13-bis-(8-quinolyl)-1,4,7,10,13-pentaoxotridecane (K-5), in combination with HTTA to extract Am(III) and Eu(III) have been recently reported by the investigators. The presence of the K-5 in the organic phase not only increased the extraction of the trivalent metals, but also showed a preference for Am(III) over Eu(III). This result was surprising since most neutral donors do not alter the selectivity of HTTA. In an effort to better understand the synergistic mechanism of the K-5/HTTA system, the thermodynamic parameters have been measured by a temperature variation method, and results are reported in this paper. 7 references.

• Research Organization: Tennessee Technological Univ., Cookeville (USA). Dept. of Chemistry; Oak Ridge National Lab., TN (USA)
• DOE Contract Number: AC05-84OR21400; AS05-79ER10489
• OSTI ID: 5919871
• Report Number(s): DOE/ER/10489-15; CONF-830808-15-Summ.; ON: DE85009116
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400105* -- Separation Procedures
ACTINIDES
AMERICIUM
DATA
ELEMENTS
ENTHALPY
ENTROPY
ETHERS
EUROPIUM
EXPERIMENTAL DATA
EXTRACTION
HETEROCYCLIC COMPOUNDS
INFORMATION
KETONES
MEDIUM TEMPERATURE
METALS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC FLUORINE COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PHYSICAL PROPERTIES
RARE EARTHS
SEPARATION PROCESSES
SOLVENT EXTRACTION
SYNERGISM
THERMODYNAMIC PROPERTIES
TRANSPLUTONIUM ELEMENTS
TRANSURANIUM ELEMENTS
TTA