The influence of pre-oxidation and leaching parameters on Iranian ilmenite concentrate leaching efficiency: Optimization and measurement

• Leaching efficiency of Iranian ilmenite was optimized for the first time.
• Two 26−2 fractional factorial designs were used to design of experiments.
• The influence of pre-oxidation treatment on leaching efficiency was evaluated.
• Fe and Ti leaching percentages were measured from forty experiments.

This research was performed to model and optimize the response of Iranian ilmenite to pre-oxidation and leaching parameters using fractional factorial design. The Ti and Fe leaching percentages were considered as leaching response with respect to leaching parameters as the particle size, temperature, time, hydrochloric acid molarity, solid to liquid ratio and stirring speed. In order to detect the effect of pre-oxidation on leaching process half of the samples were oxidized at 900 °C for 120 min. Then experiments were performed at the designed condition and consequently Ti and Fe leaching percentages were measured using an atomic absorption spectroscopy. Finally the most significant factors affected on Fe and Ti leaching percentages and optimum conditions were obtained using analysis of variance. It was concluded that using the statistical method is useful not only for optimizing and modeling the leaching parameters but also for understanding the detrimental effect of pre-oxidation on Fe and Ti extraction.