Alpha radiolysis and other factors affecting hydrolysis of tributyl phosphate

Technical Report · Sat Jun 01 00:00:00 EDT 1985

DOI:https://doi.org/10.2172/5534740· OSTI ID:5534740

Lloyd, M H; Fellows, R L

The primary purpose of this study was to identify the principal degradation products produced by Pu(IV) loading in 30% tributyl phosphate/dodecane (TBP-DD) solutions and to determine the formation rates of these species as a function of temperature. Experiments were also conducted to evaluate HNO/sub 3/ hydrolysis of TBP as a function of temperature and to compare the effects resulting from plutonium solvent loading with effects due to loading with uranium and zirconium. The results indicate that four factors are of particular significance: (1) dibutyl phosphate (DBP) is the principal plutonium-complexing species formed at temperatures of 50/sup 0/C or lower, while significant concentrations of monobutyl phosphate (MBP) are also formed at higher temperatures; (2) the TBP degradation rate due to alpha radiolysis or chemical hydrolysis is strongly dependent on temperature; (3) plutonium promotes TBP hydrolysis by two mechanisms, alpha radiolysis and metal-ion-induced hydrolysis, and, of these, metal-ion-induced hydrolysis can be the major effect; and (4) small amounts of an unidentified plutonium-complexing species are formed in experiments using plutonium of high specific activity (about 4 x 10/sup 8/ counts per minute per milligram (c/min dot mg)). This species cannot be removed from 30% TBP-DD by Na/sub 2/CO/sub 3/ washing or other solvent cleanup procedures. The TBP degradation rates (determined as grams of plutonium complexed by degradation products) increased from 0.125 mg Pu/L dot h at 25/sup 0/C to 47.9 mg Pu/L dot h at 80/sup 0/C in 30% TBP-DD solutions that contained only 0.68 M HNO/sub 3/. In solutions that additionally contained approx.20 g/L of plutonium (specific activity = 9 x 10/sup 7/ c/min dot mg) TBP degradation rates increased from 2.46 mg Pu/L dot h at 25/sup 0/C to 127.1 mg Pu/L dot h at 80/sup 0/C. 10 refs., 8 figs., 4 tabs.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5534740
• Report Number(s): ORNL/TM-9565; ON: DE85015071
• Country of Publication: United States
• Language: English

Related Subjects

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY
DODECANE
CHEMICAL REACTION YIELD
TBP
HYDROLYSIS
RADIOLYSIS
DBP
EXPERIMENTAL DATA
MEDIUM TEMPERATURE
NITRIC ACID
PLUTONIUM
PLUTONIUM COMPLEXES
TEMPERATURE DEPENDENCE
TIME DEPENDENCE
URANIUM
ZIRCONIUM
ACTINIDE COMPLEXES
ACTINIDES
ALKANES
BUTYL PHOSPHATES
CHEMICAL RADIATION EFFECTS
CHEMICAL REACTIONS
CHEMISTRY
COMPLEXES
DATA
DECOMPOSITION
ELEMENTS
ESTERS
HYDROCARBONS
HYDROGEN COMPOUNDS
INFORMATION
INORGANIC ACIDS
LYSIS
METALS
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
PHOSPHORIC ACID ESTERS
RADIATION CHEMISTRY
RADIATION EFFECTS
SOLVOLYSIS
TRANSITION ELEMENTS
TRANSURANIUM COMPLEXES
TRANSURANIUM ELEMENTS
YIELDS
050800* - Nuclear Fuels- Spent Fuels Reprocessing
400600 - Radiation Chemistry