Actinide speciation, the cornerstone of nuclear fuel cycle chemistry

France has opted to close the fuel cycle in order to recycle reusable materials and limit the quantity and harmfulness of radioactive waste. Its industrial implementation is carried out according to the PUREX process (Plutonium, Uranium, Reduction, Extraction). This article presents some recent research works, with the aim of improving the state of knowledge of actinide chemistry in solution from a fundamental point of view and in support of the development of industrial processes. After a reminder of the basic knowledge concerning the speciation of actinides in aqueous solution, the main steps of the industrial process of plutonium treatment/recycling are presented, followed by some recent examples illustrating the interest of speciation for the understanding of the chemical phenomena in some operations of the nuclear fuel cycle