SEPARATION OF PROTACTINIUM FROM THORIUM IN NITRIC ACID SOLUTIONS BY SOLVENT EXTRACTION WITH TRIBUTYL PHOSPHATE OR BY ADSORPTION ON PULVERIZED UNFIRED VYCOR GLASS OR SILICA GEL

Technical Report · Mon Apr 01 00:00:00 EST 1963

DOI:https://doi.org/10.2172/4718828· OSTI ID:4718828

Moore, J. G.; Rainey, R. H.

Two methods were investigated for the separation and recovery of Pa from short-decayed Th fuel in HNO/sub 3/ solutions. The Pa/sub 233/, Th, and U may be coextracted from highly acidic feed solutions with 30% tributyl phosphate, or the Pa may be preferentially adsorbed on pulverized unfired Vycor glass or silica gel. Major effort has been on the adsorption method. Adsorption experiments with tracer concentrations of Pa/sup 233/ in HNO/sub 3/ solutions showed distribution coefficient maxima for Pa of about 1000, 325, and 175 from 6 to 10 M HNO/sub 3/ for laboratory-prepared silica gel, unfired Vycor, and commercial silica gel, respectively. Unfired Vycor, a commercial, leached borosilicate glass containing 96% SiO/sub 2/ and about 3% B/sub 2/O/sub 3/, was used for most of the studies. Fired Vycor glass adsorbed little or no Pa. The adsorption coefficient of Pa by unfired Vycor glass from HNO/sub 3/ solutions increased as the contact time increased or as the particle size of the glass decreased and was dependent on the concentration of salt or HNO/sub 3/ in the solution. The adsorbed Pa may be eluted with oxalic or tartaric acids. Although optimum conditions for column operations were not determined, decontamination factors of Pa from Th, U, Ru, Zr- Nb and total rare earths of 6x 10/sup 3/, 1.6 x 101,4 x 10/sup 3/, 3, and 5.8 x 10/sup 5/, respectively, were obtained in tracer experiments. Batch countercurrent scouting experiments with tracer Pa showed that about 90% of the Pa was extracted with the Th and U from 5 M HNO/sub 3/-1 M Al(NO/sub 3/)/sub 3/ solutions, with a decontamination factor of 70 from Ru and about 10/sup 5/ from rare earths. (P.C.H.)

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• DOE Contract Number: W-7405-ENG-26
• NSA Number: NSA-17-020101
• OSTI ID: 4718828
• Report Number(s): ORNL-TM-543
• Resource Relation: Other Information: Orig. Receipt Date: 31-DEC-63
• Country of Publication: United States
• Language: English

Related Subjects

CHEMISTRY
ADSORPTION
ALUMINUM NITRATES
BORON SILICATES
BUTYL PHOSPHATES
COLLOIDS
DECONTAMINATION
DISTRIBUTION
GLASS
GRAIN SIZE
NIOBIUM
NITRIC ACID
ORGANIC ACIDS
OXALIC ACID
PROTACTINIUM
PROTACTINIUM 233
QUANTITATIVE ANALYSIS
RARE EARTHS
REFRACTORIES
RUTHENIUM
SILICON OXIDES
SOLUTIONS
SOLVENT EXTRACTION
TARTARIC ACID
THORIUM
TRACER TECHNIQUES
URANIUM
VYCOR
ZIRCONIUM