Demonstration of a Universal Solvent Extraction Process for the Separation of Cesium and Strontium from Actual Acidic Tank Waste at the INEEL
- Khlopin Radium Institute
- INEEL
A universal solvent extraction process is being evaluated for the simultaneous separation of Cs, Sr, and the actinides from acidic high-activity tank waste at the Idaho National Engineering and Environmental Laboratory (INEEL) with the goal of minimizing the high-activity waste volume to be disposed in a deep geological repository. The universal solvent extraction process is being developed as a collaborative effort between the INEEL and the Khlopin Radium Institute in St. Petersburg, Russia. The process was recently demonstrated at the INEEL using actual radioactive, acidic tank waste in 24 stages of 2-cm-diameter centrifugal contactors located in a shielded cell facility. With the testing, removal efficiencies of 99.95%, 99.985%, and 95.2% were obtained for Cs-137, Sr-90, and total alpha, respectively. This is sufficient to reduce the activities of Cs-137 and Sr-90 to below NRC Class A LLW requirements. The total alpha removal efficiency was not sufficient to reduce the activity of the tank waste to below NRC Class A non-TRU requirements. The lower than expected removal efficiency for the actinides is due to loading of the Ph2Bu2CMPO in the universal solvent with actinides and metals (Zr, Fe, and Mo). Also, the carryover of aqueous solution (flooding) with the solvent exiting the actinide strip section and entering the wash section resulted in the recycle of the actinides back to the extraction section. This recycle of the actinides contributed to the low removal efficiency. Significant amounts of the Zr (>97.7%), Ba (>87%), Pb (>98.5%), Fe (>6.9%), Mo (19%), and K (17%) were also removed from the feed with the universal solvent extraction flowsheet.
- Research Organization:
- Idaho National Lab. (INL), Idaho Falls, ID (United States)
- Sponsoring Organization:
- USDOE Office of Environmental Management (EM) (US)
- DOE Contract Number:
- AC07-94ID13223
- OSTI ID:
- 9296
- Report Number(s):
- INEEL/CON-99-00092; TRN: AH200122%%268
- Resource Relation:
- Conference: Global '99, Jackson, WY (US), 08/29/1999--09/03/1999; Other Information: PBD: 1 Aug 1999
- Country of Publication:
- United States
- Language:
- English
Similar Records
Demonstration of a universal solvent extraction process for the separation of actinides, cesium, and strontium from actual acidic tank waste at the Idaho National Engineering and Environmental Laboratory
Universal Solent Extraction (UNEX) Flowsheet Testing of the Removal of Cesium, Strontium, and Actinide Elements from Radioactive, Acidic Dissolved Calcine Waste
Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
54 ENVIRONMENTAL SCIENCES
AQUEOUS SOLUTIONS
CESIUM
EXTRACTION APPARATUSES
SOLVENT EXTRACTION
SOLVENTS
STRONTIUM
TANKS
WASTES
ACIDIC HIGH-ACTIVITY TANK WASTE
CENTRIFUGAL CONTACTORS
REMOVAL EFFICIENCIES
ACTINIDES
NRC CLASS A LOW-LEVEL WASTE REQUIREMENTS
UNIVERSAL SOLVENT EXTRACTION PROCESS