DIAMIDE DERIVATIVES OF DIPICOLINIC ACID AS ACTINIDE AND LANTHANIDE EXTRACTANTS IN A VARIATION OF THE UNEX PROCESS
The Universal Extraction (UNEX) process has been developed for simultaneous extraction of cesium, strontium, and actinides from acidic solutions. This process utilizes an extractant consisting of 0.08 M chlorinated cobalt dicarbollide (HCCD), 0.007-0.02 M polyethylene glycol (PEG-400), and 0.02 M diphenyl-N,N-di-n-butylcarbamoylmethylphosphine oxide (Ph2CMPO) in the diluent trifluoromethylphenyl sulfone (CF3C6H5SO2, designated FS-13) and provides simultaneous extraction of Cs, Sr, actinides, and lanthanides from HNO3 solutions. The UNEX process is of limited utility for processing acidic solutions containing large quantities of lanthanides and/or actinides, such as dissolved spent nuclear fuel solutions. These constraints are primarily attributed to the limited concentrations of CMPO (a maximum of ~0.02 M) in the organic phase and limited solubility of the CMPO-metal complexes. As a result, alternative actinide and lanthanide extractants are being investigated for use with HCCD as an improvement for waste processing and for applications where higher concentrations of the metals are present. Our preliminary results indicate that diamide derivatives of dipicolinic acid may function as efficient actinide and lanthanide extractants. The results to be presented indicate that, of the numerous diamides studied to date, the tetrabutyldiamide of dipicolinic acid, TBDPA, shows the most promise as an alternative actinide/lanthanide extractant in the UNEX process.
- Research Organization:
- Idaho National Lab. (INL), Idaho Falls, ID (United States)
- Sponsoring Organization:
- DOE - NE
- DOE Contract Number:
- DE-AC07-99ID-13727
- OSTI ID:
- 926325
- Report Number(s):
- INL/CON-07-12880; TRN: US0802539
- Resource Relation:
- Conference: Global 2007,Boise, Idaho,09/09/2007,09/13/2007
- Country of Publication:
- United States
- Language:
- English
Similar Records
Radionuclide partitioning in the modified Unex process
Aspects of the Fundamental Chemistry of Cesium Extraction from Acidic Media by HCCD
Related Subjects
ACTINIDES
CESIUM
COBALT
NUCLEAR FUELS
OXIDES
POLYETHYLENE GLYCOLS
PROCESSING
RARE EARTHS
SOLUBILITY
SOLVENTS
STRONTIUM
SULFONES
WASTE PROCESSING
actinide extractant
diamide derivatives of dipicolinic acid
lanthanide extractant
UNEX process