Influence of Pre-oxidation on Carbothermic Reduction Process of Ilmenite Concentrate

摘要

The pre-oxidation of Panzhihua ilmenite concentrate was investigated at 1073 K and 1273 K under air atmosphere. The products of the pre-oxidation at 1073 K were Fe_(2)O_(3), TiO_(2) and Fe_(2)Ti_(3)O_(9), while Fe_(2)O_(3), TiO_(2) and Fe_(2)TiO_(5) at 1273 K. The influences of pre-oxidation on the carbothermic reduction were studied at 1473 K, 1573 K, 1673 K and 1773 K under argon atmosphere. It was found that the main phases during the reduction process were Ti_(3)O_(5), Fe, Fe_(3)C, Ti_(2)O_(3) and TiC_(x)O_(y). The pre-oxidation was beneficial to the formation of TiC_(x)O_(y) phase compared to the direct carbothermic reduction without pre-oxidation. And the pre-oxidation at 1273 K was better for the carbothermic reduction than pre-oxidation at 1073 K. The rate controlling steps for the carbothermic reduction obeyed the diffusion model. After being reduced for 2 h at 1773 K, the product was changed to TiC with only little O content.