Synthesis of U3O8 and UO2 microspheres using microfluidics

Abstract

Uranium-bearing microspheres below 50µm with a narrow size distribution allows for a wider variety of fuel forms. To accommodate the smaller size, gel microspheres with a composition of UO3∙nH2O∙mNH3 were synthesized using microfluidics and subsequently converted to U3O8 and UO2. To accommodate the slower flow rates required by microfluidics, a more stable broth was established. The gelation studies resulted in a broth that was stable for more than two days at 0°C and for close to 3 h at room temperature while still gelling within 25 s. Synthesis of gel microspheres with a narrow size distribution lasted for 5 h and produced ∼0.5 g of air-dried material. The gelled microspheres were converted to U3O8 and UO2 and with sizes of 50 and 40 µm in diameter, respectively.