Abstract: A system for the cyclic storage and recovery of thermal energy utilizing a particulate bed of a decomposable heat storage material selected from the group consisting of the hydroxides of magnesium, calcium, and barium. The bed of heat storage material is confined within a container adjacent a water-permeable wall of the container. Thermal energy of chemical decomposition is stored by heating the bed of selected hydroxide to a temperature within the range of from 300.degree. C to 900.degree. C and above the decomposition temperature of the selected hydroxide for a time sufficient to decompose at least a part of the selected hydroxide to form the corresponding oxide and water vapor. The water vapor is withdrawn by passing a carrier gas into contact with the water-permeable wall of the container to absorb the water vapor permeating therethrough.

Abstract: A method is provided for producing a selected metal nitride utilizing a salt bath. The selected metal is introduced into the salt bath in the presence of gaseous nitrogen and at least a certain amount of a halide of the selected metal. The salt bath is maintained at a temperature above its melting point for time sufficient to form a precipitate of the desired amount of a nitride of the selected metal. In accordance with a preferred embodment, the pressure is thereafter reduced to less than atmospheric and the temperature increased above the boiling point of the salt for a time sufficient to volatilize the molten salt which is removed to leave a precipitate of the selected metal nitride. The method is particularly applicable to the production of the mononitrides of uranium, plutonium, thorium, and mixtures thereof.

Abstract: A cyclic method of storing and recovering thermal energy utilizing a particulate bed of a decomposable heat storage material selected from the group consisting of the hydroxides of magnesium, calcium, and barium. The bed of heat storage material is confined within a container adjacent a water-permeable wall of the container. Thermal energy of chemical decomposition is stored by heating the bed of selected hydroxide to a temperature within the range of from 300.degree. to 900.degree.C and above the decomposition temperature of the selected hydroxide for a time sufficient to decompose at least a part of the selected hydroxide to form the corresponding oxide and water vapor. The water vapor is withdrawn by passing a carrier gas into contact with the water-permeable wall of the container to absorb the water vapor permeating therethrough.