Abstract: The invention relates to a process for the processing of nuclear targets and/or fuels based on metallic aluminium by dissolving with the aid of aqueous tetramethylammonium hydroxide (TMAOH) solutions.Dissolving can consist of a total dissolving in a single stage of the core and the can of the nuclear fuel by TMAOH or a decanning of the can by TMAOH, followed by a nitric dissolving of the core. The use of TMAOH eliminates the disadvantages associated with dissolving in a concentrated nitric or sodium medium and decanning with soda and in particular permits the easy vitrification of the effluents produced by the process.

Abstract: The invention relates to a process for dissolving plutonium dioxide by means of OH.sup.- radicals produced by radiolysis of water and usable for the treatment of dissolving fines and plutoniferous waste.To this end, contacting takes place in a reactor (1) of solid products containing PuO.sub.2 coming from the hopper (5) with an aqueous nitric solution (3) irradiated by radiation or charged particles for producing OH.sup.- radicals by radiolysis of said solution, in the presence of a reagent such as N.sub.2 O, able to trap the solvated electrons and the H.sup.- radicals produced in simultaneous manner and optionally a redox mediator such as silver.Irradiation can take place by an alpha or beta emitter present in the solution or by an external source such as an irradiator or an electron accelerator.