Studies on reaction runaways for Urex/Purex solvent-nitric acid and red-oil synthesis
- Reprocessing R and D Division, Reprocessing Group, Indira Gandhi Centre for Atomic Research, Kalpakkam 603102 (India)
In PUREX/UREX processes for recycling of spent nuclear fuels, 30% TBP solvent is used, This solvent has a small solubility in the aqueous phase. During concentration of the process solutions by an evaporation route, a runaway reaction between TBP and nitric acid is initiated at above 130 deg. C, leading to rapid pressurization and finally containment failure if proper venting is not provided. Red oil was synthesized for the first time in India, and its physical properties as well as thermodynamic parameters for the reaction were determined. It was experimentally established that the presence of metallic nitrates was not essential for red-oil formation as thought earlier. Various experiments have been completed for single-phase as well as two-phase runs. The most important finding of this work was lowering of the limiting acid concentration from the conventional values. In fact, in these experiments, red oil could be formed even at 2 N aqueous acidity. Thus, safety guidelines based on the classical literature are obsolete. New guidelines for the red-oil-safety are required. (authors)
- Research Organization:
- Chemical Sciences Division, Oak Ridge National Laboratory (United States)
- OSTI ID:
- 21230390
- Resource Relation:
- Conference: ISEC 2008: International Solvent Extraction Conference on Solvent Extraction: Fundamentals to Industrial Applications, Tucson, AZ (United States), 15-19 Sep 2008; Other Information: Country of input: France; 12 refs; Related Information: In: Proceedings of ISEC 2008, International Solvent Extraction Conference - Solvent Extraction: Fundamentals to Industrial Applications, by Moyer, Bruce A. (ed.), 1740 pages.
- Country of Publication:
- United States
- Language:
- English
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