Method of preparing a synthetic rutile from a titaniferous slag containing magnesium values
AssigneeQit-Fer et Titane Inc.
InventorMichel Gueguin
Life of this patent
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Abstract
Synthetic rutile is prepared from titaniferous slags containing alkaline-earth metal impurities, such as magnesium oxide, by a method comprising contacting the slag with chlorine at a temperature of at least about 800.degree. C., and then leaching the chlorine-treated slag with hydrochloric acid at a temperature of at least about 140.degree. C.
Claims26
A method for upgrading the content of TiO.sub.2 in a titaniferous slag, the titaniferous slag containing FeO, Ti.sub.2 O.sub.3 and at least 1.0 weight percent MgO, and the molecular ratio of Ti.sub.2 O.sub.3 to FeO being at least about 1, the method comprising:
- contacting the titaniferous slag with chlorine gas at a temperature of at least about 800.degree. C. such that the slag is chlorine-treated and FeCl.sub.2 is formed;
- and
- contacting the chlorine-treated slag with hydrochloric acid such that MgCl.sub.2 is formed and the slag is hydrochloric acid-treated.
The method of claim I where the titaniferous slag before contacting with the chlorine gas is sized to a dimension suitable for fluidization.
A method for upgrading the content of TiO.sub.2 in a titaniferous slag, the titaniferous slag containing FeO, Ti.sub.2 O.sub.3 and at least 1.0 weight percent MgO, and the molecular ratio of Ti.sub.2 O.sub.3 to FeO being at least about 1, the method comprising:
- heating the slag in an inert atmosphere to a temperature of at least about 800.degree. C.;
- contacting the heated slag with chlorine gas at a temperature of at least about 800.degree. C. such that ironchlorides are formed and the titaniferous slag is chlorine-treated;
- continuing to contact the heated slag with chlorine gas for a predetermined time interval;
- cooling the chlorine-treated slag to approximately room temperature;
- contacting the chlorine-treated slag with hydrochloric acid at a temperature of at least about 140.degree. C. such that the slag is hydrochloric acid-treated;
- cooling the hydrochloric acid-treated slag;
- washing the slag;
- drying the slag;
- and
- calcining the slag such that a calcined slag is formed.
Dependencies are inferred from the claim text.