Separation of Molybdenum from Plutonium-238 Dioxide

Two methods by which molybdenum metal coatings may be removed from plutonium dioxide shards are: (a) fusion of the coated shards in a mixture of potassium nitrate and potassium hydroxide, cooling the melt, and washing the unattacked shards with water; and (b) boiling the shards in an aqueous solution of sodium hypochlorite containing a small amount of mercuric nitrate as a catalyst, and subsequently washing the unattacked shards with water. Both methods remove sufficient molybdenum from the shards (or pellets of compacted shards weighing not more than g each) so the remaining molybdenum does not pose any problems in subsequent nitric acid based recovery operations. The fusion technique generates a smaller volume of liquid waste and does not introduce chlorine into steel recovery facilities.