SOLVENT EXTRACTION SEPARATION OF NEODYMIUM AND PROMETHIUM USING DI(2-ETHYL- HEXYL)ORTHOPHOSPHORIC ACID AS EXTRACTANT

Technical Report · Sun Jul 01 04:00:00 EDT 1962

DOI:https://doi.org/10.2172/4829755· OSTI ID:4829755

Perez, B. L.; McHenry, R. E.

A multistage continuous solvent extraction process using di(2-ethyl- hexyl)orthophosphoric acid (D2EHPA) as an extractant was developed for the fractionation of the rare earths. The process was developed particularly for the separation of fission neodymium and promethium. To obtain a significant production rate with D2EHPA requires that the variation in the distribution coefficient of the solute from stage to stage (due to loading effect and pH changes) be controlled within operable limits. This can be done by using a high concentration organic phase (1 molar) and high acid aqueous phase (0.74 molar). With organic phase loading to 24% the variation in K/sub d/ does not exceed a factor of 2. Separation factors using toluene diluent and nitric acid aqueous phase were about 1.7, but the K/sub d/'s were too low for a high production rate at reasonable organic flow. With Amsco as a diluent, the separation factors were still ~1.7, but the K/sub d/'s were much higher. In the pilot-plant scale demonstration, good process stability and near theoretical separation were obtained in an 11-stage mixer-settler. (auth)

• Research Organization: Oak Ridge National Lab., Tenn.
• DOE Contract Number: W-7405-ENG-26
• NSA Number: NSA-16-023788
• OSTI ID: 4829755
• Report Number(s): ORNL-TM-184
• Country of Publication: United States
• Language: English

Related Subjects

ACIDITY
ALKYL RADICALS
AMSCO
CHEMISTRY
CONTROL
DEHPA
DISTRIBUTION
EFFICIENCY
ETHYL RADICALS
FABRICATION
FISSION PRODUCTS
LABORATORY EQUIPMENT
MIXER-SETTLERS
MIXING
NEODYMIUM COMPOUNDS
NITRIC ACID
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHORIC ACID
PILOT PLANT
PRECIPITATION
PRODUCTION
PROMETHIUM COMPOUNDS
RARE EARTHS
SEPARATION PROCESSES
SOLVENT EXTRACTION
SOLVENTS
STABILITY
TESTING
TOLUENE