Solvent degradation products in nuclear fuel processing solvents

Technical Report · Wed Jun 01 04:00:00 EDT 1988

DOI:https://doi.org/10.2172/7057142· OSTI ID:7057142

Shook, Jr, H E

The Savannah River Plant uses a modified Purex process to recover enriched uranium and separate fission products. This process uses 7.5% tri-n-butyl phosphate (TBP) dissolved in normal paraffin hydrocarbons for the solvent extraction of a nitric acid solution containing the materials to be separated. Periodic problems in product decontamination result from solvent degradation. A study to improve process efficiency has identified certain solvent degradation products and suggested mitigation measures. Undecanoic acid, lauric acid, and tridecanoic acid were tentatively identified as diluent degradation products in recycle solvent. These long-chain organic acids affect phase separation and lead to low decontamination factors. Solid phase extraction (SPE) was used to concentrate the organic acids in solvent prior to analysis by high performance liquid chromatography (HPLC). SPE and HPLC methods were optimized in this work for analysis of decanoic acid, undecanoic acid, and lauric acid in solvent. Accelerated solvent degradation studies with 7.5% TBP in normal paraffin hydrocarbons showed that long-chain organic acids and long-chain alkyl butyl phosphoric acids are formed by reactions with nitric acid. Degradation of both tributyl phosphate and hydrocarbon can be minimized with purified normal paraffin replacing the standard grade presently used. 12 refs., 1 fig., 3 tabs.

• Research Organization: Du Pont de Nemours (E.I.) and Co., Aiken, SC (USA). Savannah River Lab.
• DOE Contract Number: AC09-76SR00001
• OSTI ID: 7057142
• Report Number(s): DP-1759; ON: DE89001169
• Country of Publication: United States
• Language: English

Related Subjects

050800* -- Nuclear Fuels-- Spent Fuels Reprocessing
11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS
ALKANES
BUTYL PHOSPHATES
CARBOXYLIC ACIDS
CHEMICAL COMPOSITION
CHEMICAL REACTIONS
CLEANING
DECANOIC ACID
DECOMPOSITION
DECONTAMINATION
EFFICIENCY
ESTERS
EXTRACTION
HYDROCARBONS
MONOCARBOXYLIC ACIDS
NATIONAL ORGANIZATIONS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANIC SOLVENTS
OTHER ORGANIC COMPOUNDS
PARAFFIN
PHOSPHORIC ACID ESTERS
PUREX PROCESS
REPROCESSING
SAVANNAH RIVER PLANT
SEPARATION PROCESSES
SOLVENTS
TBP
US AEC
US DOE
US ERDA
US ORGANIZATIONS
WAXES
YIELDS