Density, actidity, and conductivity measurements of uranyl nitrate/nitric acid solutions

Conductivity, density, and acidity (pH) measurements were made on a series of uranyl nitrate solutions under conditions closely simulating the process used to load weak acid resins in the preparation of the HTGR recycle fuel particle. To relate these parameters to the uranium and nitrate concentrations of the solutions, a least-squares fit of the experimental data and mathematical expressions resulting from computer curve-fitting techniques was made. Measurements were made on solutions having concentrations of 0.05 to 1.27 M uranium, 0.1 to 2.0 M nitrate, and NO/sub 3//U ratios from 1.56 to 2.3. These measurements were made at 25, 30, 40, 50, and 75/sup 0/C. From these experiments, the necessary data were obtained to write two computer programs which can be used to predict or calculate uranium and nitrate concentrations of the process solutions and which will allow control of the process to be exercised in the particle preparation.