Study on cleaning solvents using activated alumina in PUREX process

Abstract

Abstract The PUREX process is used to extract uranium and plutonium from dissolved solutions (spent nuclear fuel liquor). The extractant is 30% tributyl phosphate in n-dodecane, which is known to be degradable by radiation and nitric acid. Tributyl phosphate degradation products can generally be washed in alkali solutions like sodium carbonate solution; however, it is more difficult to remove n-dodecane degradation products using this method. A method of cleaning solvents using activated alumina is discussed in this study. A degradation sample of 30% TBP/n-dodecane was prepared by irradiating (1.6 MGy) with a 60Co gamma-source. The degradation products were then qualitatively analyzed using a gas chromatography-mass spectrometer (GC-MS). After being irradiated the solvents were cleaned with activated alumina, and a phase separation test with performed in evaluating the cleaned solvent. This resulted in the discovery of a procedure for the removal of n-dodecane degradation products of dodecanol and dodecanone, with about 70% of the degradation products, and the phase separation performance could be clearly improved through use of activated alumina.