GB715257A - Improvements in or relating to the separation of iron from titaniferous iron ores - Google Patents

Abstract

In a process for separating the iron from the titanium values in a titaniferous iron ore containing ferrous oxide, the ore is treated with an oxidizing agent and the oxidized ore is then treated with titanium tetrachloride at a temperature of at least 500 DEG C. to form volatile ferric chloride which is removed and titanium dioxide which remains. Chlorine may be used as an oxidizing agent and the chlorine supplied simultaneously with the titanium tetrachloride. In an example of this form of the process, preheated ore is charged into a reactor and a mixture of chlorine and titanium tetrachloride vapour, preheated to 250-350 DEG C. is passed upwards through the ore bed at sufficient velocity to fluidize it. Additional ore, preheated to 300-400 DEG C., is then supplied to the reactor so that the reaction takes place at 500-1200 DEG C. and the volatilized ferric chloride passes off while titanium dioxide remains in the reactor. Slightly above, and at least 10 per cent. above, the stoichiometric proportions are used for the titanium tetrachlorides and chlorine respectively. The titanium dioxide may be chlorinated in the same reactor or transferred to another where it is suspended in the presence of carbon and chlorine, to form titanium tetrachloride, and the ferric chloride may be collected and oxidized to form chlorine for use in the process. Oxygen may be used as the oxidizing agent for the ore and in one example of this form of the process, the ferrous oxide in the ore is oxidized by roasting in air. A fluidized bed is formed in the reactor by passing titanium tetrachloride vapour through at sufficient velocity and additional ore is added to the bed so that the reaction takes place at 850-1050 DEG C. The titanium tetrachloride used is slightly in excess of the stoichiometric proportion and is preferably mixed with an equal quantity of an inert gas, e.g. nitrogen. In small plant, electric heating elements may be used for the reactor.ALSO:In a process for separating the iron from the titanium values in a titaniferous iron ore containing ferrous oxide the ore is treated with an oxidizing agent and the oxidized ore is then treated with titanium tetrachloride at a temperature of at least 500 DEG C. to form volatile ferric chloride which is removed. Chlorine may be used as an oxidizing agent and the chlorine supplied simultaneously with the titanium tetrachloride. In an example of this form of the process, preheated ore is charged into a reactor and a mixture of chlorine and titanium tetrachloride vapour, preheated to 250-350 DEG C., is passed upwards through the ore bed at sufficient velocity to fluidise it. Additional ore, preheated to 300-400 DEG C. is then supplied to the reactor so that the reaction takes place at 500-1200 DEG C. and the volatilized ferric chloride passes off while titanium dioxide remains in the reactor. Slightly above, and at least 10 per cent. above the stoichiometric proportions are used for the titanium tetrachloride and chlorine respectively. The titanium dioxide may be chlorinated in the same reactor, or transferred to another where it is suspended in the presence of carbon and chlorine, to form titanium tetrachloride, and the ferric chloride may be collected and oxidized to form chlorine for use in the process. Oxygen may be used as the oxidizing agent for the ore and in an example of this form of the process, the ferrous oxide in the ore is oxidized by roasting in air. A fluidized bed is formed in the reactor by passing the titanium tetrachloride through at sufficient velocity and additional ore is added to the bed so that the reaction takes place at 850-1050 DEG C. The titanium tetrachloride used is slightly in excess of the stoichiometric proportion and is preferably mixed with an equal quantitly of an inert gas, e.g. nitrogen. In small plant electric heating elements may be used for the reactor.