Experimental study of ruthenium volatilization from boiling nitric solution

As part of study of the volatilization ruthenium behaviour in a boiling nitric solution, this paper presents the results of experiments dealing with the influence of different parameters (Ru and HNO 3 concentrations, temperature, water addition) and the effect of in-situ inhibitors to mitigate potential releases. The amount of Ru volatilized from a nitric solution heated at 130 °C is about 2% of initial inventory. The addition of a low amount of inhibitors allowed to prevent ruthenium volatilization. Alternative strategies examined to restrict volatilization are the temperature decrease and the “water feed”, this later is more efficient.