Résumé
Sonochemistry (i.e., chemical reactions driven under power ultrasound) has attracted considerableattention as a promising alternative in nuclear reprocessing due to the mild and efficient reactionconditions it enables. The arising acoustic cavitation, (i.e., the nucleation, growth, and rapid implosivecollapse of gas and vapor-filled micro-bubbles) allows the in-situ generation of active species that canreact in solution and lead to redox interactions. In heterogeneous systems, this phenomenon goes withstrong physical effects such as erosion of surfaces, grain fractures, increase of mass transfer, and decreaseof diffusion layers. This presentation aims to summarize the investigations carried out in the topic of Pusonochemistry since 2010 at ICSM and At alante facilities in Marcoule. The talk will focus on (i) theredox behavior of Pu(III), Pu(IV), Pu(V), and Pu(VI) ions in aqueous nitric solutions under ultrasoundirradiation, (ii) the ultrasound-assisted reductive dissolution of refractory PuO2, and (iii) the sonochemicalpreparation of stable and salt-free nanometric Pu colloids (Figure 1). Related characterizations areperformed with UV-Vis absorption spectroscopy, SEM, HR-TEM, EXAFS and XANES.