The Universal Solvent Exchange (UNEX) Process II: Flowsheet Development & Demonstration of the UNEX Process for the Separation of Cesium, Strontium, and Actinides from Actual Acidic Radioactive Waste

Journal Article · Mon Jan 01 04:00:00 EST 2001 · Solvent Extraction and Ion Exchange

DOI:https://doi.org/10.1081/SEI-100001371· OSTI ID:912115

Law, Jack Douglas; Herbst, Ronald Scott; Todd, Terry Allen; Romanovskiy, V N; Smirnov, I V; Esimantovskiy, V M; N, Zaitsev B; Babain, V A

A novel solvent extraction process, the Universal Extraction (UNEX) process, has been developed for the simultaneous separation of cesium, strontium, and the actinides from acidic waste solutions. The UNEX process solvent consists of chlorinated cobalt dicarbollide for the extraction of 137Cs, polyethylene glycol for the extraction of 90Sr, and diphenyl-N,N-dibutylcarbamoyl phosphine oxide for the extraction of the actinides and lanthanides. A nonnitroaromatic polar diluent consisting of phenyltrifluoromethyl sulfone has been developed for this process. A UNEX flowsheet consisting of a single solvent extraction cycle has been developed as a part of a collaborative effort between the Khlopin Radium Institute (KRI) and the Idaho National Engineering and Environmental Laboratory (INEEL). This flowsheet has been demonstrated with actual acidic radioactive tank waste at the INEEL using 24 stages of 2-cm diameter centrifugal contactors installed in a shielded cell facility. The activities of 137Cs, 90Sr, and the actinides were reduced to levels at which a grout waste form would meet NRC Class A LLW requirements. The extraction of 99Tc and several nonradioactive metals by the UNEX solvent has also been evaluated.

• Research Organization: Idaho National Laboratory (INL)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC07-99ID13727
• OSTI ID: 912115
• Report Number(s): INEEL/JOU-00-00870
• Journal Information: Solvent Extraction and Ion Exchange, Journal Name: Solvent Extraction and Ion Exchange Journal Issue: 1 Vol. 19; ISSN 0736-6299; ISSN SEIEDB
• Country of Publication: United States
• Language: English

Related Subjects

99 GENERAL AND MISCELLANEOUS
ACTINIDES
CESIUM
COBALT
EXTRACTION APPARATUSES
FLOWSHEETS
GROUTING
LIQUID WASTES
PHOSPHINE OXIDES
POLYETHYLENE GLYCOLS
RADIOACTIVE WASTES
RADIUM
RARE EARTHS
SOLVENT EXTRACTION
SOLVENTS
STRONTIUM
SULFONES
TANKS
Universal Extraction (UNEX)
WASTE FORMS
WASTES
actinides
radioactive waste
solvent