Solid-state reaction of strontium oxalate with uranium oxalate

Uranyl oxalate and strontium oxalate were synthesized and characterized. Reaction of strontium oxalate with uranyl oxalate was studied by employing simultaneous TG/DTA. It has been observed that uranyl oxalate decomposes into mixture of U3O8 and UO2.13 with the evolution of carbon monoxide, oxygen and carbon dioxide in the temperature range of 573–673 K, but beyond this temperature U3O8 and UO2.13 appeared as intermediates and the final product has been found to be UO2.12. Oxalates of strontium and uranium were taken in the mole ratio of 1:1 to study the solid-state reaction. The products of the reactions have been identified. In the presence of uranium oxide, strontium oxalate first decomposes to strontium carbonate followed by the reaction of the carbonate with uranium oxide at a relatively high temperature during the next step in TG. XRD characterization of the intermediates and end products indicated that SrUO4 is formed, which gets partially reduced to SrUO3 at elevated temperature.