Preparation of U3O8 by Calcination from Ammonium Uranyl Carbonate Using Response Surface Methodology: Process Optimization

The parameters to prepare U3O8 by calcination from ammonium uranyl carbonate were optimized by using response surface methodology. A quadratic equation model for the value of total uranium and U4+ of triuranium octaoxide was built and the effects of main factors and their corresponding relationships were obtained. The statistical analysis of the results indicated that the value of total uranium and U4+  of triuranium octaoxide was significantly affected by the calcination temperature and calcination time in this study range. The optimized calcination conditions were determined as follows: the calcination temperature961.6 K, the calcination time 27.9 min, and the mass of material 37.86 g, respectively. Under these conditions, the value of total uranium and U4+  of triuranium octaoxide was 84.29% and 28.14%. The validity of the model was confirmed experimentally and the results were satisfactory.