Lithium isotope enrichment by electrochemical pumping using solid lithium electrolytes

Concentrating Li-6 isotopes, which exist only approximately 7.6% in nature, to 40 to 90%, is necessary for development of thermal fusion reactors, which are promising as next-generation base-load energy systems. We investigated the possibility of Li-6 enrichment by electrochemical pumping using La0.57Li0.29TiO3 solid lithium electrolytes. We also clarified the influence of potential application profiles on separation efficiency. Giving a potential difference to electrodes prepared on both sides of the electrolyte made the electrode on the lithium solution side positive and concentrated Li-6. The efficiency of lithium isotope enrichment was affected by the potential application profile. An intermittent potential application concentrates Li-6 with high efficiency. In an intermittent potential application in which the electrode on the lithium solution side was positive, an Li-6 concentration with higher efficiency was achieved when a small negative potential was applied to the lithium solution side electrode while suspending application of the positive potential. (C) 2018 The Ceramic Society of Japan. All rights reserved.