Influence of temperature of precipitation on agglomeration and other powder characteristics of ammonium diuranate

Batch precipitation of ammonium diuranate (ADU) was carried out at various temperatures and at different flow rates of ammonia and their effects on th e characteristics of ADU such as the nature of settling, moisture content, ammonia-to-uranium mole ratio and nitrate content have been studied. The ef fect of temperature of precipitation and the technological significance of savings in terms of heating requirements and quantity of precipitating agen t ammonium hydroxide has been brought out. Also, the influence on other men tioned characteristics has been viewed in this angle. An attempt is made to explain the agglomeration of ADU semi-quantitatively, in terms of second o rder reaction kinetics by classifying the conditions of precipitation into two distinct phenomena, namely, the diffusion and activation controlled mec hanisms. The activation energy involved in agglomeration of ADU under the e xperimental conditions was also calculated. (C) 2001 Elsevier Science B.V. All rights reserved.