Extraction studies of selected actinide ions from aqueous solutions with 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione and tri-n-octylphosphine oxide

Conference · Fri Nov 01 04:00:00 EST 1991

OSTI ID:10135429

Hannink, N J; Hoffman, D C ^[1]; Smith, B F ^[2]

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1. Lawrence Berkeley Lab., CA (United States)
2. Los Alamos National Lab., NM (United States)

The first measurements of distribution coefficients (K{sub d}) for Cm(III), Bk(III), Cf(III), Es(III), and Fm(III) between aqueous perchlorate solutions and solutions of 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione (BMPPT) and the synergist tri-n-octylphosphine oxide (TOPO) in toluene are reported. Curium-243, berkelium-250, californium-249, einsteinium-254, and fermium-253 were used in these studies. The K{sub d} for {sup 241}Am was also measured and is in agreement with previously published results. Our new results show that the K{sub d}`s decrease gradually with increasing atomic number for the actinides with a dip at Cf. In general, the K{sub d}`s for these actinides are about a factor of 5 to 10 greater than the K{sub d}`s for the homologous lanthanides at a pH of 2.9, a BMPPT concentration of 0.2 M, and a TOPO concentration of 0.04 M. The larger K{sub d}`s for the actinides are consistent with greater covalent bonding between the actinide metal ion and the sulfur bonding site in the ligand.

• Research Organization: Lawrence Berkeley Lab., CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 10135429
• Report Number(s): LBL--31566; CONF-910812--15; ON: DE92010267
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
400105
400702
ACTINIDES
AQUEOUS SOLUTIONS
BERKELIUM
BERKELIUM 250
CALIFORNIUM
CALIFORNIUM 249
CHEMICAL BONDS
CHEMICAL PROPERTIES
CURIUM
CURIUM 243
DISTRIBUTION
EINSTEINIUM
EINSTEINIUM 254
EXTRACTION
FERMIUM
FERMIUM 253
PERCHLORATES
PH VALUE
PHASE STUDIES
PHOSPHINE OXIDES
PROPERTIES OF RADIOACTIVE MATERIALS
SEPARATION PROCEDURES
SEPARATION PROCESSES
SULFUR COMPOUNDS