Abstract: Disclosed is a process for making a cinder aggregate from neutralized PUREX waste. The PUREX waste is concentrated to about 30 to about 40 percent solids and a colloid of such de-alcoholated alkoxides of silicon, boron, and aluminum are added to the PUREX waste as are necessary to produce a mixture containing about 0.0001 to about 1 percent aluminum hydroxide, about 5 to about 15 percent silica, and about 1 to about 3 percent boric oxide. The resulting mixture is heated to about 400 to about 700.degree. C. which produces a cinder. The cinder will be transported to a vitrification center where it can be disintegrated in ammonium hydroxide and the nuclear waste can be permanently encapsulated in glass.

Abstract: Disclosed is a method of making a pellet from a powder by placing the powder in a heat-shrinkable container, sealing the container and isostatically pressing the container at a temperature which causes it to shrink, followed by decomposition of the container and sintering of the powder. In preparing nuclear fuel pellets, a free-flowing fissile powder is mixed with a free-flowing fertile powder and the mixture is placed in the heat-shrinkable container. The container is sealed, heated and isostatically pressed, then decomposed and the powder is sintered.

Abstract: Disclosed is a method of immobilizing nuclear waste in glass. A composition is prepared of 60 to 100% of a hydrolyzed glass-forming silicon compound and up to about 40% of a glass-forming aluminum compound. About 1 to about 50% liquid nuclear waste and up to about 10% solid nuclear waste is mixed into the composition. The composition is heated at about 200.degree. to about 500.degree. C. to drive off water and organics, with the resulting vitreous product totally containing the nuclear waste. Finally, this product can be sintered at about 800.degree. to about 900.degree. C. to reduce porosity, or warm pressed into block form.

Abstract: Disclosed is a method of immobilizing nuclear waste in glass. A composition is prepared of about 30 to about 85% of a hydrolyzed glass-forming silicon compound, about 5 to about 30% of a glass-forming sodium compound, up to about 30% of a glass-forming aluminum compound, and about 5 to about 30% of a glass-forming boron, calcium, or magnesium compound. Up to an equal amount of nuclear waste is mixed into the composition and the mixture is heated at up to 500.degree. C. until dry. The mixture is then melted at 800.degree. to 1300.degree. C., and can be poured into ingots and cooled. The mixture can also be melted in situ with a laser.