Determination of solubility limit of CrF₂ in IMSBR coolant salt FLiNaK

The Molten Salt Breeder Reactors (MSBR) is a class of generation IV nuclear reactor, where the proposed fuel (2 mol% UF₄+ 20 mol% ThF₄ + 78 mol% LiF) and coolant (46.5 mol% LiF + 11.5 mol% NaF + 42 mol% KF) are in the form of molten salt. In order to predict long term compatibility of coolant salt with structural material (hastelloy-N), it is necessary to analyse corrosion behaviour of structural material in FLiNaK at reactor operating temperature i.e. 1073 K. Among all the components of hastelloy-N, Chromium is least immune for attack by FLiNaK because of its favourable thermodynamic and dissolution kinetics. The mass loss of Ni based alloys is found to decrease in the order Cr²⁺2+2+. Hence, in the present study, solubility limit of Cr²⁺ in FLiNaK has been determined