Process for obtaining ammonium uranyl carbonate for the preparation of uranium dioxide as a fuel for nuclear reactors

摘要

In the process of the invention, a uranium compound reacts with ammonium ions and carbonate ions in aqueous solution. According to the invention, a first aqueous solution (71) which contains ammonium ions and carbonate ions is admixed over a first period with an aqueous solution (12) prepared from uranyl fluoride for precipitating a first amount of ammonium uranyl carbonate, and thereafter over a second period is admixed with an aqueous solution (12) of uranyl fluoride while at least essentially at the same time a second aqueous solution (13) is fed in which contains higher concentrations of ammonium ions and carbonate ions than the first aqueous solution, in order to precipitate the bulk of the ammonium uranyl carbonate. IMAGE