摘要
Titanium dioxide （TiO2） was recovered from ilmenite （FeO-TiO2） contained in ferrotitaniferous sands of Mompiche area, by the combination of the thermal treatments of oxidation and carbothermic reduction and the subsequent leaching with hydrochloric acid （HCI） of the thermally treated samples. This study was developed because of the large source of TiO2 that Ecuador has, but has not developed enough research to place an industry to produce this compound. The oxidation at 900 ℃ for 3 h yielded a content of 11% of TiO2, and the highest oxidation of ilmenite （82%） was achieved at 1,000 ℃ for 1 h. The carbothermic reduction with 15wt% carbon at 950 ℃ for 2 h achieved a content of 6% TiO2 and 21% ilmenite. The combination of thermal treatments did not increase the content of TiO2 but allowed to obtain more soluble minerals in HCl. The best results of leaching were obtained with 100 mL of 256 g/L HC1 for 6 h at 70 ℃ and 10% solids of the sample oxidized at 900 ℃ for 3 h and subsequently reduced with 15wt% carbon at 950 ℃ for 2 h. The optimum leaching time was 4 h, giving a TiO2 of 90% purity with a recovery of 43%.
