The paper presents results of reduction of rutile and ilmenite concentrate by CH_4-H_2-Ar gas mixture and chlorination of reduced rutile and ilmenite by Cl_2-N_2 gas mixture. Reduction was investigated in a laboratory fixed bed reactor in temperature-programmed and isothermal experiments. The use of methane-containing gas with high carbon activity (above unity relative to graphite) provided strongly reducing conditions in which titanium oxide was reduced to titanium oxycarbide in the following sequence: TiO_2 → Ti_5O_9 → Ti_4O_7 → Ti_3O_5 → Ti_2O_3 → TiO_xC_((1-x)). At 1400-1500°C, extent of reduction of titania to titanium oxycarbide, defined as percentage of oxygen removed, achieved more than 85% (approximately 70 wt% TiC) in about 90 min. The product of reduction of ilmenite concentrate contained metallic iron and titanium oxycarbide. The reduction of iron oxides to metallic iron preceded carburization of titanium oxides, and the metallic iron catalyzed methane cracking and deposition of solid carbon. Chlorination of reduced rutile and ilmenite was tested at 200°C and 480°C. Extent of chlorination of titanium oxycarbide produced by reduction of rutile achieved 52% in 50 min at 200°C and 80% in 20 min at 480°C.
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