DRAMATIC IMPROVEMENTS IN CAUSTIC-SIDE SOLVENT EXTRACTION OF CESIUM THROUGH MORE EFFICIENT STRIPPING

Conference · Tue Jan 01 04:00:00 EST 2008

OSTI ID:941595

Delmau, Laetitia Helene ^[1]; Bazelaire, Eve ^[1]; Bonnesen, Peter V ^[1]; Engle, Nancy L ^[1]; Gorbunova, Maryna ^[1]; Haverlock, Tamara ^[1]; Moyer, Bruce A ^[1]; Ensor, Dale ^[2]; Meadors, Viola M ^[1]; Harmon, Ben ^[2]; Bartsch, Richard A. ^[3]; Surowiec, Malgorzata A. ^[3]; Zhou, Hui ^[3]

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1. ORNL
2. Tennessee Technological University
3. Texas Tech University, Lubbock

Dramatic potential improvements to the chemistry of the Caustic-Side Solvent Extraction (CSSX) process are presented as related to enhancement of cesium stripping. The current process for removing cesium from the alkaline high-level waste (HLW) at the USDOE Savannah River Site employs acidic scrub and strip stages and shows remarkable extraction and selectivity properties for cesium. It was determined that cesium stripping can be greatly improved with caustic or near-neutral stages using sodium hydroxide and boric acid as scrub and strip solutions, respectively. Improvements can also be achieved by appending pH-sensitive functional groups to the calix[4]arene-crown-6 extractant. Addition of a proton-ionizable group to the calixarene frame leads to a dramatic "pH swing" of up to 6 orders of magnitude change in cesium distribution ratio.

• Research Organization: Oak Ridge National Laboratory (ORNL)
• Sponsoring Organization: SC USDOE - Office of Science (SC)
• DOE Contract Number: AC05-00OR22725
• OSTI ID: 941595
• Country of Publication: United States
• Language: English

Related Subjects

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
BORIC ACID
CALIXARENES
CESIUM
HIGH-LEVEL RADIOACTIVE WASTES
RADIOACTIVE WASTE PROCESSING
SODIUM HYDROXIDES
SOLVENT EXTRACTION