Interaction of celestine concentrate and reagent grade SrSO₄ with oxalate solutions

The interaction of reagent grade strontium sulphate and celestine concentrate with aqueous solutions of oxalic acid, sodium oxalate and ammonium oxalate for the production of strontium carbonate were investigated for different oxalate compound:SrSO₄ mole ratios and reaction times using x-ray diffraction analysis and dissolution tests. Under the same experimental conditions, it was found that aqueous oxalic acid and sodium oxalate solutions had no or little effect on reagent grade strontium sulphate or celestine concentrate, but aqueous ammonium oxalate solution converted them into strontium oxalate hydrate. Strontium carbonate was obtained at conversion ratios of 74.7% for the celestine concentrate and 84.6 % for the reagent grade strontium sulphate by the decomposition of the obtained strontium oxalate hydrate at 600 °C under air atmosphere.