Novel dissymmetric N,N-dialkylamides which meet the following formula (I):
where R represents a linear or branched alkyl group at C
8
to C
15
. A method for synthesizing these N,N-dialkylamides, and to the uses of same as extractants, alone or in admixture, in order to extract uranium and/or plutonium from an aqueous acid solution, or to totally or separate uranium from plutonium from an aqueous acid solution and, in particular, an aqueous solution resulting from dissolving spent nuclear fuel in nitric acid. Further, a method for processing an aqueous solution resulting from the dissolution of a spent nuclear fuel in nitric acid, allowing the uranium and plutonium contained in the solution to be extracted, separated and decontaminated in a single cycle, without requiring any plutonium reduction operation, and in which one of the aforementioned N,N-dialkylamides or a mixture of same is used as extractant. Applications for the method include the processing of spent nuclear fuels, in particular comprising uranium (e.g. UOX) or uranium and plutonium (e.g. MOX).
新颖的不对称N,N-二烷基酰胺,符合以下公式(I):其中R代表C8到C15的直链或支链烷基基团。一种合成这些N,N-二烷基酰胺的方法,以及将其作为萃取剂单独使用或与其他物质混合以从
水酸性溶液中萃取
铀和/或
钚,或者从
水酸性溶液中完全或分离
铀和
钚,特别是从用
硝酸溶解废核燃料后得到的
水酸性溶液。此外,提供一种处理用
硝酸溶解废核燃料后得到的
水溶液的方法,允许在单个循环中提取、分离和脱污该溶液中含有的
铀和
钚,无需进行任何
钚还原操作,并且其中使用上述N,N-二烷基酰胺或其混合物之一作为萃取剂。该方法的应用包括处理废核燃料,特别是包含
铀(如UOX)或
铀和
钚(如MOX)的废核燃料。