Smelting of titaniferous iron ore and ilmenite

摘要

Titaniferous iron ore or concentrate is smelted to form iron and a slag containing titanium and little iron, fluxing exclusively with silica. Preferably, 0.5-1.5 parts of silica, including that initially in the ore, are present for each part by weight of titania, the additions of silica which may take the form of a non-titaniferous siliceous iron ore being made wholly or partly when the reduction burden is at 1450 DEG C. or above. The carbonaceous reducing agent is preferably added when the fluxed charge is molten, in sufficient quantity for selective reduction of the iron ore or in excess so as to reduce titania to the monoxide or carbide. To recover titania and alumina the slag is crushed to 100 mesh and digested with boiling 40-60% sulphuric acid, or instead of crushing it may be chlorinated directly provided the liquid slag is water granulated on leaving the furnace. Following acid digestion the filtrate is evaporated to 60% sulphuric acid, cooled to room temperature, and aluminium sulphate which crystallises out is removed by filtration. The titanous sulphate solution may be diluted with water and boiled to form hydrolysed titanium hydroxide which may be separated and calcined to produce titania.ALSO:Titaniferous iron ore or concentrate is smelted to form iron and a slag containing titanium and little iron, fluxing exclusively with silica. Preferably, 0.5-1.5 parts of silica, including that initially in the ore, are present for each part by weight of titania, the additions of silica which may take the form of a non-titaniferous siliceous iron ore being made wholly or partly when the reduction burden is at 1450 DEG C. or above. The carbonaceous reducing agent is preferably added when the fluxed charge is molten, in sufficient quantity for selective reduction of the iron ore or in excess so as to reduce titania to the monoxide or carbide.