Hematite solubility in sulfuric acid from 130-170 C and 230-270 C

Accurate hematite solubility data is required to allow the metals industry to monitor the efficiency of their iron removal processes and to better predict hematite precipitate size distribution and morphology. Hematite solubility data has been generated for 0.1-0.7 molal H2SO4 solutions at 130-170°C and 230-270°C. These measurements represent an improvement over previous experimental data due to better in-situ filtration of samples and inhibition of ferric iron reduction on titanium. Ferric iron reduction has been studied to evaluate the inflationary effect of ferrous iron on hematite solubility measurements. Suitable inhibitors to prevent ferric iron reduction have been investigated. The generated hematite solubility data has been used to construct a solution chemistry model using OLI software. A combined magnesium-hematite solubility model is then constructed to validate the proposed iron solution chemistry model. Deviations between the current work and previous hematite solubility data are explained in terms of experimental set-up.