Patent Number: 061750514
Section: abstract

Liquid metal coolants, such as alkali metal used in nuclear reactor systems can be safely deactivated to form a disposable solid waste material. The alkali metal is dissolved in an ammoniacal liquid, such as anhydrous liquid ammonia to form a reaction mixture comprising alkali metal cations and solvated electrons. A precipitating agent that ionizes in the liquid ammonia is introduced into the reaction mixture to combine with the alkali metal cations and/or solvated electrons to form a precipitating alkali metal salt. Additionally, solidified alkali metal remaining within the coolant system after initial drainage of liquid alkali metal can be dissolved by circulating an ammoniacal liquid within the coolant system. Removal of the liquid ammonia having the alkali metal dissolved therein is combined with a ionizable precipitating agent to form a alkali metal salt.