Thermal and electrochemical process for metal production
View Patent ↗A system for purification of high value metals comprises an electrolytic cell in which an anode formed of a composite of a metal oxide of the metal of interest with carbon is electrochemically reduced in a molten salt electrolyte.
1. A method for the production of titanium metal which comprises electrochemically dissolving, in a molten salt electrolyte, an anode formed of a titanium suboxide/carbon composite, and reducing the dissolved titanium suboxide, at a cathode, to titanium metal.
2. The method of claim 1 , wherein said molten salt electrolyte comprises a strong Lewis acid.
3. The method of claim 2 , wherein the electrolyte is selected from the group consisting of an eutectic of sodium chloride, lithium chloride and potassium chloride, an eutectic of potassium fluoride, sodium fluoride and lithium fluoride, an eutectic of sodium chloride, calcium chloride and potassium chloride, an eutectic of sodium chloride, magnesium chloride and sodium fluoride, and an eutectic of sodium chloride, potassium chloride and sodium fluoride.
4. A method for the production of purified titanium from rutile ore which comprises electrowinning from an anode formed of a mixture of titanium suboxide/carbon composite in a molten salt electrolyte, and depositing purified titanium onto a cathode.
5. The method of claim 4 , wherein the molten salt electrolyte is selected from the group consisting of an eutectic of sodium chloride, lithium chloride and potassium chloride, an eutectic of potassium fluoride, sodium fluoride and lithium fluoride, an eutectic of sodium chloride, calcium chloride and potassium chloride, an eutectic of sodium chloride, magnesium chloride and sodium fluoride, and an eutectic of sodium chloride, potassium chloride and sodium fluoride.
6. The method of claim 4 , wherein titanium suboxide is mixed with carbon in a ratio of at least 1:1.5 over stoichiometry to produce TiC and CO 2 /CO.
7. The method of claim 4 , wherein the titanium suboxide is mixed with carbon in a ratio of at least 1:1 over stoichiometry to produce TiC and CO 2 /CO.
8. A method for the production of purified titanium which comprises electrochemically dissolving an anode formed of a titanium suboxide/carbon composite in a molten salt electrolyte, and electrochemically reducing the dissolved titanium suboxide to purified titanium metal.
9. The method of claim 8 , wherein the molten salt electrolyte is selected from the group consisting of an eutectic of sodium chloride, lithium chloride and potassium chloride, an eutectic of potassium fluoride, sodium fluoride and lithium fluoride, an eutectic of sodium chloride, calcium chloride and potassium chloride, an eutectic of sodium chloride, magnesium chloride and sodium fluoride, and an eutectic of sodium chloride, potassium chloride and sodium fluoride.
10. The method of claim 8 , wherein titanium suboxide is mixed with carbon in a ratio of at least 1:1.5 over stoichiometry based on titanium to produce TiC and CO 2 /CO.
11. The method of claim 8 , wherein the titanium suboxide is mixed with carbon in a ratio of at least 1:1 over stoichiometry based on titanium to produce TiC and CO 2 /CO.
12. The method of claim 8 , wherein titanium suboxide-carbon composite anode is formed by heating a titanium oxide with carbon under an inert atmosphere.
13. The method according to claim 8 , wherein the anode comprises a composite of titanium suboxide and carbon, and including the step of adding a Ti +2 containing compound to the electrolyte.
14. A method for the direct production of titanium metal in a particulate state which comprises electrochemically dissolving an anode, formed of a titanium suboxide/carbon composite, in a molten salt electrolyte in an electrochemical cell, and electrochemically reducing the dissolved titanium suboxide to particulate titanium metal.
15. The method of claim 14 , wherein said molten salt electrolyte comprises a strong Lewis acid.
16. The method of claim 15 , wherein the electrolyte is selected from the group consisting of an eutectic of sodium chloride, lithium chloride and potassium chloride, an eutectic of potassium fluoride, sodium fluoride and lithium fluoride, an eutectic of sodium chloride, calcium chloride and potassium chloride, an eutectic of sodium chloride, magnesium chloride and sodium fluoride, and an eutectic of sodium chloride, potassium chloride and sodium fluoride.
17. The method of claim 14 , wherein the electrolyte includes a Ti +3 containing compound which is reduced in one step to titanium metal.
18. The method of claim 17 , wherein the Ti +3 containing compound is added in a concentration of ½ to 20% by weight of the electrolyte.
19. The method of claim 18 , wherein the Ti +3 containing compound is added in a concentration of 1 to 10% by weight of the electrolyte.
20. The method according to claim 14 , wherein the electrode is formed of a titanium oxide/carbon composite, and including the step of adding a Ti +2 containing compound to the electrolyte.
21. The method of claim 20 , wherein the Ti +2 containing compound is added in a concentration of ½ to 20% by weight of the electrolyte.
22. The method of claim 21 , wherein the Ti +2 containing compound is added in a concentration of 1 to 10% by weight of the electrolyte.
23. A method for the production of titanium metal which comprises electrochemically dissolving, in a molten salt electrolyte, an anode formed of a titanium oxide/carbon composite, wherein the molten salt electrolyte comprises a strong Lewis acid, and electrochemically reducing the dissolved titanium oxide to titanium metal at a cathode.
24. The method of claim 23 , wherein the electrolyte is selected from the group consisting of an eutectic of sodium chloride, lithium chloride and potassium chloride, an eutectic of potassium fluoride, sodium fluoride and lithium fluoride, an eutectic of sodium chloride, calcium chloride and potassium chloride, an eutectic of sodium chloride, magnesium chloride and sodium fluoride, and an eutectic of sodium chloride, potassium chloride and sodium fluoride.
25. A method for the direct production of titanium metal in a particulate state which comprises electrochemically dissolving an anode, formed of a titanium oxide/carbon composite, a molten salt electrolyte in an electrochemical cell, wherein the molten salt electrolyte comprises a strong Lewis acid, and electrochemically reducing the dissolved titanium oxide to titanium metal.
26. The method of claim 25 , wherein the electrolyte is selected from the group consisting of an eutectic of sodium chloride, lithium chloride and potassium chloride, an eutectic of potassium fluoride, sodium fluoride and lithium fluoride, an eutectic of sodium chloride, calcium chloride and potassium chloride, an eutectic of sodium chloride, magnesium chloride and sodium fluoride, and an eutectic of sodium chloride, potassium chloride and sodium fluoride.
27. The method according to claim 25 , wherein the electrode is formed of a titanium oxide/carbon composite, and including the step of adding a Ti +2 containing compound to the electrolyte.
28. The method of claim 27 , wherein the Ti +2 containing compound is added in a concentration of ½ to 20% by weight of the electrolyte.
29. The method of claim 28 , wherein the Ti +2 containing compound is added in a concentration of 1 to 10% by weight of the electrolyte.
30. The method of claim 25 , wherein the electrolyte includes Ti +3 containing compound which is reduced in one step to titanium metal.
31. The method of claim 30 , wherein the Ti +3 containing compound is added in a concentration of ½ to 20% by weight of electrolyte.
32. The method of claim 31 , wherein the Ti +3 containing compound is added in a concentration of 1 to 10% by weight of the electrolyte.