Precipitation and dissolution kinetics and equilibria of aqueous ferrous carbonate vs temperature

Abstract In this research, aqueous ferrous carbonate, FeCO 3 , was studied in a batch reactor designed to maintain rigorously anoxic conditions in the absence of reducing agents. The precipitation kinetics were measured from 27 to 80°C and were found to be approximately 100 times slower than any measured precipitation rate previously reported for a 2:2 sparingly soluble salt. Dissolution kinetics results are reported at 26 and 60°C. Solubility product constant measurements are reported from 25 to 94°C. Statistical analyses and application of the Nielsen theory of surface reaction rates suggest that the precipitation of ferrous carbonate is surface reaction rate limited with an Arrhenius activation energy of 108.3 kJ/mol. The dissolution of ferrous carbonate is probably also surface reaction rate limited.