On the durability of Pt coated Ti electrodes for the electro-oxidative dissolution of spent nuclear fuels

Abstract

The main objective of this study is to assess the long-term performance of Pt nanoparticle coated anodised Ti coupons which are used for electrochemical dissolution of spent mixed-oxide nuclear fuels during reprocessing. In this work, electrodes were exposed to a simulated dissolver solution containing a representative fraction of low-activity actinides and fission products in 11.5 N nitric acid in a mock-up of the service dissolver vessel. Platinum nanoparticles were coated onto anodised titanium coupons through a seed-mediated hydrothermal method. The coated coupons were then exposed in the simulated dissolver solution for about 1185 h at 110°C. Morphological and compositional analyses confirmed the presence of metallic Pt nanoparticles on the electrode surface with some localised cracking. The electrochemically active surface area of the Ptnanoparticle coated anodised titanium coupon after exposure was found to be twice that of polycrystalline platinum thus establishing the durability and efficiency of the coating on the electrode.