Effect of acetohydroxamic acid on the extraction of plutonium by dilute tri-n-butyl phosphate/n-dodecane in the presence of a high concentration of Al(NO3)3

Acetohydroxamic acid (AHA) is a hydrophilic organic complexing agent with excellent masking or stripping effects on the tetravalent actinides in the extraction operations. Therefore, AHA is a promising reagent for the spent nuclear fuel reprocessing. In the reprosessing of spent uranium-aluminum fuel with a high U-235 enrichment which is used in research reactor, the dissolver solution contains a high concentration of Al(NO 3 ) 3 , several orders of magnitude higher than that of minor actinides such as plutonium, and dilute tri-n-butyl phosphate(TBP)/n-dodecane is adopted as the extractant. In this research, complexation of Pu(IV) with AHA under the condition of U-Al fuel reprocessing is investigated. Results show that Al(NO 3 ) 3 insignificantly affects the mentioned complexation reaction. Further, the possibility of uranium purification against Pu(VI) is also investigated by using AHA in the presence of a high concentration of Al(NO 3 ) 3 by simulating some experiments on the separation process.