Patent Number: 040642046
Section: claims

1. A method for making nuclear fuel rods comprising forming a matrix comprising graphite flour, pitch a viscosity reducing additive additive, combining said matrix with nuclear fuel particles to provide a molding mixture, placing said molding mixture in a mold and compressing said molding mixture while heating said molding mixture to a temperature of from about 100.degree. C to about 300.degree. C, to form a nuclear fuel rod, said additive being selected from the group consisting of saturated and unsaturated alcohols having a carbon chain length of from 12 to 20, saturated and unsaturated fatty acids having a carbon chain length of from 12 to 20, saturated and unsaturated primary amines derived from fatty acids having a carbon chain length of from 12 to 20 and saturated hydrocarbons derived from petroleum having a molecular weight in the range of from about 350 to about 1400, said additive being present at a level of from about 2 to about 12 percent by weight of said matrix, said graphite flour being present at a level of from about 25 to about 45 percent by weight of said matrix, and said pitch being present at a level of from about 43 to about 73 percent by weight of said matrix. 2. A method in accordance with claim 1 wherein said additive is selected from the group consisting of 1-octadecanol, 1-hexadecanol, oleic acid, stearic acid, 1-octadecylamine, petrolatum, and mixtures thereof. 3. A method in accordance with claim 1 wherein said additive is present in said matrix at a level of from about 5 to about 10 percent by weight. 4. A method in accordance with claim 1 wherein said matrix has a viscosity of less than about 1000 poises as determined by a capillary viscometer at a temperature of 175.degree. C and a wall shear rate of 100 sec.sup.-1. 5. A method in accordance with claim 1 wherein said fuel rod releases from said mold with a shear stress of less than about 50 psig. 6. A method for making nuclear fuel rods comprising forming a matrix said matrix comprising graphite flour, pitch and a viscosity reducing additive additive, heating said matrix to a temperature of from about 100.degree. C to about 300.degree. C and injecting said matrix into a mold containing nuclear fuel particles to form a nuclear fuel rod, said additive being selected from the group consisting of saturated and unsaturated alcohols having a carbon chain length of from 12 to 20, saturated and unsaturated fatty acids having a carbon chain length of from 12 to 20, saturated and unsaturated primary amines derived from fatty acids having a carbon chain length of from 12 to 20 and saturated hydrocarbons derived from petroleum having a molecular weight in the range of from about 350 to about 1400, said additive being present at a level of from about 2 to about 12 percent by weight of said matrix, said graphite flour being present at a level of from about 25 to 45 percent by weight of said matrix, and said pitch being present at a level of from about 43 to 73 percent by weight of said matrix. 7. A method in accordance with claim 6 wherein said additive is selected from the group consisting of 1-octadecanol, 1-hexadecanol, oleic acid, stearic acid, 1-octadecylamine, petrolatum, and mixtures thereof. 8. A method in accordance with claim 6 wherein said additive is present in said matrix at a level of from about 5 to about 10 percent by weight. 9. A method in accordance with claim 6 wherein said matrix has a viscosity of less than about 1000 poises as determined by a capillary viscometer at a temperature of 175.degree. C and a wall shear rate of 100 sec.sup.-1. 10. A method in accordance with claim 6 wherein said fuel rod releases from said mold with a shear stress of less than about 50 psi.