A Pulse Radiolysis Investigation of the Reactions of Tributyl Phosphate with the Radical Products of Aqueous Nitric Acid Irradiation

Journal Article · Tue Jul 01 04:00:00 EDT 2008 · Journal of Physical Chemistry A.

DOI:https://doi.org/10.1021/jp802169v· OSTI ID:935229

Mincher, Bruce J; Mezyk, Stephen R; Martin, Leigh R

Tributyl phosphate (TBP) is the most common organic compound used in liquid-liquid separations for the recovery of uranium, neptunium, and plutonium from acidic nuclear fuel dissolutions. The goal of these processes is to extract the actinides while leaving fission products in the acidic, aqueous, phase. However, the radiolytic degradation of TBP has been shown to reduce the separation factors for fission products, and to impede the back-extraction of the actinides during stripping. As most previous investigations of the radiation chemistry of TBP have focused on steady state radiolysis and stable product identification, with dibutylphosphoric acid (HDBP) invariably being the major product, here we have determined room temperature rate constants for the reactions TBP and HDBP with the hydroxyl radical ((5.00 +/- 0.02) x 109, (4.40 +/- 0.10) x 109), hydrogen atom ((1.8 +/- 0.2) x 108, (1.1 +/- 0.1) x 108), nitrate radical ((4.3 +/- 0.7) x 106, (2.9 +/- 0.2) x 106) and nitrite radical (< 2 x 105, < 2 x 105) M-1 s-1 with TBP and HDBP, respectively. These data are used to discuss the mechanism of TBP radical-induced degradation.

• Research Organization: Idaho National Laboratory (INL)
• Sponsoring Organization: DOE - NE
• DOE Contract Number: AC07-99ID13727
• OSTI ID: 935229
• Report Number(s): INL/JOU-08-13987
• Journal Information: Journal of Physical Chemistry A., Journal Name: Journal of Physical Chemistry A. Journal Issue: 28 Vol. 112
• Country of Publication: United States
• Language: English

Related Subjects

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
ACTINIDES
ATOMS
FISSION PRODUCTS
HYDROGEN
HYDROXYL RADICALS
IRRADIATION
NEPTUNIUM
NITRATES
NITRIC ACID
NITRITES
NUCLEAR FUELS
ORGANIC COMPOUNDS
PLUTONIUM
RADIATION CHEMISTRY
RADICALS
RADIOLYSIS
TBP
URANIUM
radiolysis