A study on morphology and chemical composition of precipitates produced from UO2(NO3)2-(NH4)2CO3 solution

Abstract Four types of precipitates with different chemical composition and morphology were obtained from the reaction of (NH 4 ) 2 CO 3 with UO 2 (NO 3 ) 2 solution. A phase diagram has been made and crystal structure and chemical composition of each phase has been characterized by using SEM, X-ray, IR and thermal analysis. It was found that ammonium uranyl carbonate, (NH 4 ) 4 UO 2 (CO 3 ) 3 , with monoclinic crystal morphology can be synthesized when the mole ratio of (NH 4 ) 2 CO 3 U in the solution is higher than 5.