Destruction of soluble organics generated during the dissolution of sintered uranium carbide by mediated electrochemical oxidation process

Abstract

Abstract The destruction of soluble carbonaceous compounds formed during the dissolution of sintered uranium mono carbide pellets in 11.5 M nitric acid at 65 °C has been investigated by employing mediated electrochemical oxidation (MEO) method, in which process 0.05 and 0.01 M Ag(II) and 0.1 and 0.06 M Ce(IV) were used as the regenerable catalysts. The current density and temperature of the process for maximum destruction efficiency were optimized to be 25 mA/cm2 and 75 °C respectively. The electro-oxidation behaviour of the mediator ions Ag(II) and Ce(IV) with respect to their concentration in the removal of organics and the dependence of temperature on the stabilities of the two electrochemical catalysts were compared. The effect of fission product elements in a synthetic dissolver solution on the performance of Ag(II) mediator in oxidizing the carbon content was discussed. The destruction efficiency of MEO process in eliminating the soluble organics was ascertained to be better than that of direct electrochemical oxidation method as well as prolonged oxidation of the organics with concentrated nitric acid.