Study of the Changes in Composition of Ammonium Diuranate with Progress of Precipitation, and Study of the Properties of Ammonium Diuranate and its Subsequent Products Produced from both Uranyl Nitrate and Uranyl Fluoride Solutions

摘要

Uranium metal used for fabrication of fuel for research reactors in India is generally produced by magnesio-thermic reduction of UF 4 . Performance of magnesio-thermic reaction and recovery and quality of uranium largely depends on properties of UF 4 . As ammonium diuranate (ADU) is first product in powder form in the process flow-sheet, properties of UF 4 depend on properties of ADU. ADU is generally produced from uranyl nitrate solution (UNS) for natural uranium metal production and from uranyl fluoride solution (UFS) for low enriched uranium metal production. In present paper, ADU has been produced via both the routes. Variation of uranium recovery and crystal structure and composition of ADU with progress in precipitation reaction has been studied with special attention on first appearance of the precipitate Further, ADU produced by two routes have been calcined to UO 3 , then reduced to UO 2 and hydroflorinated to UF 4 . Effect of two different process routes of ADU precipitation on the characteristics of ADU, UO 3 , UO 2 and UF 4 were studied here.