Study on extraction of iron from chromite

Research about extraction of iron from chemical-grade South African chromite by carbothermic reduction and hydrochloric acid leaching was conducted in this study. It was found that temperature had a remarkable effect on the extraction yield of iron and that the optimum experimental temperature was 1100 °C, which coincides with the theoretically predicted value. The effect of reduction duration and the process of precipitate development at 1100 °C were also investigated. It was found that selective reduction of iron reached near completion within 2 h with only minor loss of chromium. Results also demonstrated that 20% hydrochloric acid was strong enough to extract iron from the reduction product selectively and at the same time increased the porosity of the chromium-rich solid particle. Ultimately, there is a clear improvement of the Cr/Fe ratio, Cr₂O₃% and specific surface area of chromite, and magnetite was obtained as by-product.