Separation of Rare Earth Elements From Simulated Spent Fuels by Flotation Process Using Ionic Liquid

Effective separation of rare earth elements(REs, neutron poisons) from spent nuclear fuels is the key step in recycle of spent nuclear fuel. In the present study, the organic twophase with ionic liquid used for the flotation separation of rare earths from simulated spent fuels was provided firstly. U₃O₈ and rare earths oxide will not be dissolved in these liquids during the flotation process. The flotation system contain kerosene(oleic acid) as an diluent, P507 as collector, ［C₄mim］［PF₆］ and ［C₄mim］［Tf₂N］. The optimal experimental condition of flotation separation was obtained. Rare earths oxide will be removed from the mixture and the amount will be minimized after several flotation cycles. It was found that the density of rare earth oxide(REO) had important influence on the ratio of REs removal from the mixture. Based on above, the flotation separation using one stage flotation machine was also conducted. The results show that the ratio of Nd removal can reach more than 80%.