Dust-Free Fabrication of Uranium and Plutonium Oxide Powders for Radioisotope Systems, Nuclear Thermal Rockets, Nuclear Electric Propulsion, and Surface Power Reactors

This SBIR project will develop a manufacturing method for nuclear fuels that can be universally applied for space-power systems that utilizes a dust-free uranium oxide production unit. For the particular application to nuclear thermal propulsion, in which one wishes, (1) to maximize hydrogen propellant heating, and (2)to reduce fission product gas release and reactor particulates into the engines exhaust stream, ifan ensemble of fine particles can be controllable fabricated in solution and bonded into a solid during solution drying, then the radiation-hazard can also be avoided. Furthermore, having fine control over the particulate geometry can allow one to tailor the fuel geometry such that the hydrogen heating is maximized and the fission-product gas release is minimized.The fabrication technology will achieve high through-put granule formation without the formation of hazardous particulates in an aqueous solution via either internal gelation sol-gel methods or colloidal assembly. Previous work with cerium, a surrogate for uranium and plutonium, has demonstrated the production of monodisperse microspheres (~ 3 % diameter uncertainty) of cerium dioxide, showing that the desired sizes can be produced, purity requirements can be met, and that pressurized water treatments modify microsphere properties such that they do not produce fines or strongly agglomerate during heat treatments. Nanostructured metal-oxides provide pathway through which higher purities and greater densification can be achieved. During Phase I, we will optimize the starting material recipe for the high-throughput growth of stable, conductive fuel-pellets, using cerium oxide as a uranium surrogate, so that the uranium oxide fuel manufacturing process can be optimized during Phase II.