The Impact of Uranium–Thorium Nitric Acid Solution Concentration on the Properties of Powders Produced by Thermochemical Denitration

The impact of the concentration of the initial nitric acid actinide solutions on the thermochemical denitration in a thin-film rotary apparatus, on the entrainment of actinides into a local gas purification system, and on the physicochemical and some technological characteristics of the obtained uranyl(VI)–thorium formate powders (with thorium taken as a plutonium simulator) was determined. At the initial U + Th concentration in the solution of 200 g/L, the productivity was 65.20 g/h, the bulk density with/without tapping was 841 ± 45/704 ± 31 g/dm3, and the specific surface area was 0.69 ± 0.07 m2/g. The particle shape is predominantly spheroidal, which, in our opinion, will favor good fluidity of the powder during the reduction in a rotary tube furnace installed in the existing production facility for producing a pilot batch of uranium–plutonium oxide fuel.