From waste to resource, nuclear rare metals as a dream of modern alchemists

Fission reaction of 235U will generate more than 40 elements and 400 nuclides in the spent fuel. Among them, Ru, Rh, Pd, Tc, Mo, Cs, Sr and lanthanides (Lns) are rich in the spent fuel and are categorized as nuclear rare metal (NRM). Typical yields of Pd, Ru, Rh and Tc will reach to around 11 kg, 13 kg, 4 kg and 3 kg, respectively per metric ton of the reference fast reactor spent fuel. Especially, Mo and Lns (Dy, Er, Yb) are non-radioactive and non-exothermic elements at the separation after 5 years cooling. Stable isotopes like 99Ru, 102Ru, 103Rh, 106Pd and 107Ag can be obtained without isotope separation if proper element separation of Ru/Pd, Rh/Ru, Pd/Ag, Tc/Ru will be applied. In modern utilization of the NRM, the first step is the separation from the high level liquid wastes (HLLW), and catalytic electrolytic extraction (CEE) method is applicable. The paper suggests the reality of the recycle of the NRM, with a recommendation to use light platinum group (Pt-G) and Tc after proper stockpile. The extensive separation of NRM (along with actinides (Ans) and long-lived fission products (LLFP)) would not only open a new direction in fuel cycle missions, but also drastically improve current radioactive waste management.