Laboratory Investigations in Support of Fluid Bed Fluoride Volatility Processes. Part I. The Fluorination of Uranium Dioxide-Plutonium Dioxide Solid Solutions

LABORATORY INVESTIGATIONS IN SUPPORT OF FLUID-BED FLUORIDE VOLATILITY PROCESSES. PART XVI. THE FLUORINATION OF UO$sub 2$--PuO$sub 2$-FISSION-PRODUCT OXIDE PELLETS WITH FLUORINE IN A 2-INCH-DIAMETER FLUID-BED REACTOR.

“…In previous studies of the reuse of alumina beds, a recycle- 6,7 fluorination sequence of 5 hr at 450'C, 5 hr at 5000C, and 10 hr at 550'C was required for effective plutonium removal from each batch of fuel added to the alumina bed. Before the recycle-fluorination step, an initial fluorination step was used in which most of the uranium as well as about half the plutonium was volatilized.…”

“…A pellet-to-alumina charge ratio of 0.6, consisting of 1100 g of alumina and 650 g of pellets (containing 560 g uranium and 2.8 g plutonium), was generally used in an experiment. The two-zone step was usually carried out at 450°C for 3 hr using 20 N/0 oxygen and 10 v/0 fluorine; in the separati oxidation and fluorination steps, the pellets were initially oxidized for 4 hr at 450°C with 20 v/0 oxygen and then fluorinated for 2 hr at 350°C with [5][6][7][8][9][10][11][12][13][14][15][16].v/0 fluorine. With either method, approximately 80-100% of the uranium and about 20-75% of the plutonium in the pellet charge were reacted after completion of the initial fluorination step.…”