Molten Salt Reactor Chemistry: Structure and Equilibria

Molten salts are a class of ionic liquids which have in recent years been the focus of extensive fundamental research given that they are a versatile class of reaction media with a variety of appealing thermophysical and thermochemical properties (e.g. melting points, heat capacities, vapor pressures, densities, thermal conductivities, etc..) suited for a variety of industrial applications, in particular at high temperature. Themost wellknown is perhaps the production of materials as important as aluminum and sulfuric acid, yet thermal energy storage is also a notable application. One of the most noteworthy application of molten salts, is as fuel and coolant for a type of nuclear fission reactor known as theMolten Salt Reactor (MSR). In its most general sense, aMSR is a class of nuclear reactor in which fissile (235U, 233U, 239Pu) and/or fertile isotopes (e.g. 232Th, 238U) are dissolved in a carrier salt. The resulting mixture acts both as fuel and coolant. The two prototypes which have been built in the past used a fluoride fuel, so historicallymost work has concentrated on fluoride salt mixtures. However,modern day reactor developers are also interested in chloride fuels, so both molten salt fuel families are relevant at present...