Method for removing cesium from a nuclear reactor coolant

A method for removing cesium from a liquid metal circulating through a primary cooling system of a nuclear reactor comprising:

• providing a primary carbon packing trap in said primary system, continually absorbing cesium from said coolant onto said carbon packing trap at a relatively low temperature until said trap is substantially saturated with cesium, isolating said primary trap when saturated from said primary system by disconnecting said trap therefrom and connecting said primary trap to a closed regeneration flow system having a secondary carbon packing trap, said closed regeneration flow system being completely isolated from said primary coolant system and having a volume substantially smaller than said primary coolant system, increasing the temperature of the coolant passing through said primary trap, diffusing a portion of the cesium inventory on the surface of said primary trap further into the matrix thereof while dispersing a portion of said cesium inventory into said coolant circulating through said regeneration flow system, reducing the temperature of said coolant passing through said secondary trap, and physically and chemically absorbing cesium from the coolant in said regeneration flow system onto said secondary carbon packing trap until cesium equilibrium between said traps is reached whereby the primary trap is reconditioned for further usage when reconnected to the primary system.