Abstract: A geographically distributed apparatus and process for detritiating heavy water is provided. The apparatus and process provide a remote site enrichment plant for producing an enriched stream of DT/D.sub.2 gas and a hydriding unit for forming a hydride of the DT/D.sub.2 gas for transportation. Pure tritium gas is produced at a local tritium extraction plant by reforming DT/D.sub.2 in a de-hydriding unit and passing the gas mixture through a chain of cryogenic distillation columns. The invention provides a safe and cost-effective method of detritiating heavy water.

Abstract: A method of preparing active, sinterable, finely-divided plutonium oxide (PuO.sub.2) powder from plutonium metal is disclosed. The process yields plutonium fissile material which can be easily blended to form a uniformly homogeneous powder for the fabrication of high-quality light water reactor ceramic fuel pellets. Such homogeneous fuels are required to prevent hot spots from developing in a reactor using the fuel.

Abstract: The invention provides a new high temperature isotopic exchange fuel processing loop for tritium recovery in which tritium is exchanged out of impurities such as tritiated ammonia, methane and water by swamping with H.sub.2 and isotopically equilibrating the mixture in a high temperature reactor. Downstream of the reactor is a Pd/Ag permeator for separation of the hydrogen from the impurities, the separated hydrogen being sent to an isotope separation system for tritium recovery and the residual impurities being recycled. The process eliminates the need for impurity oxidation and electrolysis of DTO and does not rely on complicated catalytic decomposition reactions.

Abstract: A mixture of uranium dioxide and additive of aluminosilicate composition is formed into a compact and sintered to produce a nuclear fuel wherein the uranium dioxide grains have an average grain size of at least about 20 microns and wherein substantially all of the grains are each enveloped by glassy aluminosilicate phase.

Abstract: A particulate mixture of uranium dioxide and additive of magnesium silicate composition is formed into a compact and sintered to produce a nuclear fuel wherein the uranium dioxide grains have an average grain size of at least about 20 microns and wherein substantially all of the grains are each enveloped with glassy magnesium silicate phase.

Abstract: A particulate mixture of uranium dioxide and additive of magnesium aluminosilicate composition is formed into a compact and sintered to produce a nuclear fuel wherein the uranium dioxide grains have an average grain size of at least about 20 microns and wherein substantially all of the grains are each enveloped with glassy magnesium aluminosilicate phase.

Abstract: A method of decladding an assembly comprising an element selected from the group consisting of uranium, thorium and mixtures thereof, clad in stainless steel, zirconium, or an alloy consisting essentially of zirconium and containing minor amounts of nickel, chromium, tin, iron or combinations thereof. In a first step the cladding is scored or perforated to expose the selected element. Thereafter, the assembly is exposed to a hydrogen atmosphere at an elevated temperature for a time sufficient for the hydrogen and selected element to react and form a hydride. The temperature then is further increased to decompose the hydride back to gaseous hydrogen and the selected element. The hydriding-dehydriding preferably are repeated at least two additional times to ensure complete release of any volatile gases present.

Abstract: Uranium dioxide powder is prepared by the AUC (ammonium uranyl carbonate) method. Supplementing the known process steps, the AUC, after separation from the mother liquor, is washed with an ammonium hydrogen cabonate or an NH.sub.4 OH solution and is subsequently post-treated with a liquid which reduces the surface tension of the residual water in an AUC. Such a liquid is, for instance, alcohol.