Synthesis of U 3 O 8 and UO 2 microspheres using microfluidics *

Uranium-bearing microspheres below 50 mu m with a narrow size distribution allows for a wider variety of fuel forms. To accommodate the smaller size, gel microspheres with a composition of UO 3 center dot nH 2 O center dot mNH 3 were synthesized using microfluidics and subsequently converted to U 3 O 8 and UO 2 . 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 degrees 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 U 3 O 8 and UO 2 and with sizes of 50 and 40 mu m in diameter, respectively.