ABSTRACT
A molten salt reactor (MSR) is a reactor in which fluorides of fissile and fertile elements such as UF4, PuF3, and ThF4 are combined with carrier salts to form a fluid fuel. MSRs can operate as simple burner reactors with high fuel economy or with the addition of online fission product removal and can achieve breeder status. MSRs have numerous potential advantages over solid fuel reactors. MSRs were developed primarily at Oak Ridge National Laboratories beginning in the late 1940s. Decades of funded research and development followed a design evolution leading to the adoption in the late 1960s of what is known as the single fluid, graphite-moderated molten salt breeder reactor. While the unique aspect of liquid-fueled operation is at the core of many of the benefits of MSRs, there are of course a number of potential operational issues and challenges unique to the MSR concept.
