Method for separating ruthenium and technetium in radioactive solution and reprocessing process for spent nuclear fuel using the same

摘要

PURPOSE:To omit a refining process and simplify a reprocessing process by separatively removing ruthenium (Ru) and technetium (Tc), included in a radioactive solution, simultaneously under interaction from the solution. CONSTITUTION:Silicon carbide (SiC) powder 52 as a semiconductor catalyst and methanol as a reduction assisting agent are added into a radioactive solution 51 containing Ru and Tc, and left while being agitated. The electrons of valence band of SiC are excited by a conduction band by the action of radiation, and apparent electron holes remain in the valence band. Both electrons and electron holes are emitted into the solution from the SiC powder surface. The electrons reduces noble metal element ion such as Ru high in reduction potential to metal, to metal and deposit this on the surface of the SiC powder, and Tc ion is also reduced to metal or a dioxide and deposited. In this case, noble metal such as the previously deposited Ru accelerates the reduction- deposition of Tc by catalytic action.