Separation and utilization of rare metal fission products (RMFP) in nuclear spent fuel was studied to apply as a catalyst for hydrogen generation by water electrolysis. The RMFP, Pd, Ru, Rh and Tc, etc, are abundant, more than ca. 30kg per metric ton of a typical fast breeder reactor (FBR) spent fuel. The RMFP can be selectively separated from high level liquid waste (HLLW) by catalytic electrolytic extraction (CEE) method. Specific metallic cation such as Pd2+, which originate in the solutions, may act as promoters (i.e., Pdadatom) or mediators, thereby accelerating electrochemical deposition of RuNO3+, Rh3+ and ReO4- (simulator TcO4-). Current maximum deposition ratios of RMFP by CEE were 95-99% for Pd, 60% for Ru, >99% for Rh, 55% for Re and 25% for Tc, respectively in the nitric acid media. Electro-deposited electrodes were successively dedicated to the water (alkali or sea water) electrolysis tests. The Pd-Ru-Rh-Re mixture deposit electrodes from the solution composition of Pd:Ru:Rh:Re =3.5:4:1:1 showed the lowest initial hydrogen over potential with the highest cathodic currents in the given potential, thereby suggesting to alternate with the existing catalysts for hydrogen generation. The paper will conclusively propose RMFP, generated by nuclear fission reaction, as potential material for hydrogen production in a novel vision to bridge nuclear and hydrogen energy systems.
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