Treatment of raw materials containing titanium
AssigneeSolex Research Corporation
InventorsMorio Watanabe, Sanji Nishimura
Life of this patent
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Abstract
Production of titanium dioxide which is characterized by recovery of reusable H.sub.2 SO.sub.4, highly pure Fe oxide and hydroxide and fractional recovery of Mn, V and Cr, etc., from FeSO.sub.4. nH.sub.2 O and waste acid of 20 - 40% H.sub.2 SO.sub.4 containing abundant heavy metallic ions, which are by-produced in the production of TiO.sub.2 by dissolution of Ti raw materials such as ilmenite, steel production slag, such as electric furnace slag, convertor slag with H.sub.2 SO.sub.4.
Claims7
In a method for obtaining titanium dioxide from titanium-containing raw materials wherein the materials are dissolved in sulfuric acid to form an aqueous solution of sulfuric acid containing dissolved titanium and other metals selected from the group consisting of iron, V, Mn, Cr, and Nb, and then forming a precipitate of FeSO.sub.4 .nH.sub.2 O and the titanium in the solution is isolated and subsequently recovered as titanium dioxide from the aqueous solution, the improvement which comprises:
- 1. extracting Cr.sup.3+ and Nb.sup.5+ ions from the aqueous solution by contacting the aqueous solution with a first organic solvent selected from the group consisting of primary, secondary, tertiary and quaternary amines;
- 2. separating the aqueous solution resulting from step (1) and separating a major portion of the titanium ion in the solution by hydrolysis;
- 3. separating the aqueous solution resulting from the hydrolysis treatment of step (2) and extracting the titanium ions remaining in the aqueous solution with a second organic solvent selected from the group consisting of alkyl phosphoric acids mixed with from 2 to 5 percent higher alcohols and aromatic, aliphatic or paraffinic hydrocarbons as a diluent;
- 4. separating the aqueous solution resulting from the extraction of step (3), oxidizing the Fe.sup.+2 ions therein to Fe.sup.+3 ions and then extracting the Fe.sup.+3 ions with a third organic solvent selected from the group consisting of alkyl phosphoric acids in combination with from 2 to 5 percent higher alcohols and aromatic, aliphatic or paraffinic hydrocarbons as a diluent;
- 5. separating the aqueous solution resulting from step (4) and extracting the vanadium ions and other remaining heavy metal ions with a fourth organic solvent selected from the group consisting of primary, secondary, tertiary or quaternary amines in combination with from 2 to 5 percent higher alcohols and aromatic, aliphatic or paraffinic hydrocarbons as a diluent;
- and then
- 6. recovering, regenerating and concentrating the sulfuric acid remaining in the aqueous solution resulting from step (5).
In a method for obtaining titanium dioxide from titanium-containing raw materials wherein the materials are dissolved in sulfuric acid to form an aqueous solution of sulfuric acid containing dissolved titanium and other metals selected from the group consisting of iron, V, Mn, Cr, and Nb, and then forming a precipitate of FeSO.sub.4.nH.sub.2 O and the titanium in the solution is isolated and subsequently recovered as titanium dioxide from the aqueous solution, the improvement which comprises:
- 1. extracting Cr.sup.3+ and Nb.sup.5+ ions from the aqueous solution by contacting the aqueous solution with a first organic solvent selected from the group consisting of primary, secondary, tertiary and quaternary amines;
- 2. separating the aqueous solution resulting from step 1. and separating a major portion of the titanium ion in the solution by hydrolysis;
- 3. separating the aqueous solution resulting from the hydrolysis treatment of step 2. and extracting the titanium ions remaining in the aqueous solution with a second organic solvent selected from the group consisting of alkyl phosphoric acids mixed with from 2 to 5 percent higher alcohols and aromatic, aliphatic or paraffinic hydrocarbons as a diluent;
- 4. separating the aqueous solution resulting from the extracting of step 3., oxidizing the Fe.sup.+2 ions therein to Fe.sup.+3 ions, adding HCl to the resulting solution to form an iron chloride complex and then extracting the complex from the solution with a fifth organic solvent suitable for dissolving and extracting said complex;
- 5. separating the aqueous solution resulting from step 4. and extracting the vanadium and other remaining heavy metal ions with a fourth organic solvent selected from the group consisting of primary, secondary, tertiary, or quaternary amines, in combination with from 2 to 5 percent higher alcohols and aromatic, aliphatic or paraffinic hydrocarbons as a diluent;
- and then
- 6. recovering, regenerating and concentrating the sulfuric acid remaining in the aqueous solution resulting from step 5.
Dependencies are inferred from the claim text.