US3074860A - Electrolytic process for the production of metallic titanium from aqueous solution of titanium compounds - Google Patents
Electrolytic process for the production of metallic titanium from aqueous solution of titanium compounds Download PDFInfo
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- US3074860A US3074860A US1455A US145560A US3074860A US 3074860 A US3074860 A US 3074860A US 1455 A US1455 A US 1455A US 145560 A US145560 A US 145560A US 3074860 A US3074860 A US 3074860A
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- titanium
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- C—CHEMISTRY; METALLURGY
- C25—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
- C25C—PROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
- C25C1/00—Electrolytic production, recovery or refining of metals by electrolysis of solutions
- C25C1/22—Electrolytic production, recovery or refining of metals by electrolysis of solutions of metals not provided for in groups C25C1/02 - C25C1/20
Definitions
- My invention relates to a process for the production of metallic titanium, and more particularly to an electrolytic process for the production of metallic titanium.
- Metallic titanium is now produced by a dry method. There have been made many attempts to obtain metallic titanium by a wet method but none has succeeded. Thus, up to the present, production of metallic titanium by electrolysis of an aqueous solution of its compound has been considered as a very difiicult problem.
- My novel process for the production of metallic titanium from an aqueous solution of titanium compounds comprises a water-soluble titanium compound in which titanium which has a valency of two or three is employed as the starting material.
- the compound is converted into a titanium compound in which titanium has a valency of two by reduction by means of a reducing metal or agent, or by electrolytic reduction, or by the combination of said two reduction methods, and the titanium compound in which titanium has a valency of two thus converted from a titanium compound in which titanium has a valency of three or a titanium compound in which titanium has a valency of two in itself is made alkaline such that a sufficient reducing condition will exist in the electrolyte solution during the electrolysis operation, and it is then electrolyzed.
- water-soluble titanium in which titanium has a valency of two or three may be used.
- a titanium compound in which the valency of titanium is three it is preferable to use such a titanium compound which can easily be converted into a titanium compound in which the valency of titanium is two, for example, halides, complex salts, etc.
- the compound is converted into a titanium compound in which titanium has a valency of two by means of a reducing metal or agent or by electrolytic reduction or by the combination of said two reduction methods.
- Titanium compounds in which titanium has a valency of three have the advantage that they are more stable and more easily obtainable.
- the compound when a titanium compound in which titanium has a valency of three is employed, the compound must be converted into a titanium compound having a valency of two before electrolysis by employing a reducing metal or agent or by electrolytic reduction or by the combination of said two reduction methods.
- the reduction can be accomplished by the use of sponge titanium, or formaldehyde, or hydrazine hydrate, or pyrogallic acid, or by combinations of two of these reducing agents. It may be also accomplished by electrolytic reduction either by itself or in combination with the use of one of the aforementioned reducing agents.
- An aqueous solution of a water-soluble titanium compound in which titanium has a valency of two which 3,074,860 Patented Jan. 22, 1963 may be a titanium compound in which titanium has a valency of two in itself, or a titanium compound in which titanium has a valency of two which has been converted from a titanium compound in which titanium has a valency of three, must be adjusted so as to be alkaline.
- the aqueous alkaline solution is then subjected to electrolysis. When the electrolysis is carried out with the solution alkaline such that a sufficient reducing condition exists in the electrolyte solution metallic titanium having a high purity is deposited on the cathode.
- Example I An aqueous solution suitable for the electrolytic production of metallic titanium was prepared by dissolving 35 grams of titanium dichloride in 300 cc. of commercial aqueous formaldehyde solution, adding to the solution 10 grams of pyrogallic acid and then aqueous ammonia or caustic alkali to make the solution alkaline.
- Example 11 To 300 cc. of an alcoholic solution of titanium trichloride were added 300 cc. of commercial aqueous formaldehyde solution and then 15 grams of pulverized sponge titanium. The mixture was heated at about 50 C. When the reduction was completed, the mixture was cooled and 10 grams of pyrogalli-c acid were added. Then, aqueous ammonia was added to make the solution alkaline. The resultant solution was used as the electrolyte solution for the production of metallic titanium according to my process.
- Example 111 To 300 cc. of an aqueous solution of titanium borofluoride (titanium content 20.28 grams/liter) 50 cc. of thioglycollic acid were added and the resultant solution was electrolytically reduced using a carbon anode. When the reduction had proceeded to a point at which the solution turned to brown in color, the electrolysis was stopped. 10 grams of pyrogallic acid were added and then the solution was made alkaline by the addition of aqueous ammonia. The resultant solution was used as the electrolyte solution for the production of metallic titanium according to my process.
- Example IV To 300 cc. of a solution of titanium trihydroxide in commercial aqueous formaldehyde solution (titanium content 18.73 grams/liter) grams of pyrogallic acid were added, and the resultant solution was subjected to the electrolytic reduction in the same manner as described in Example III. The resultant solution was made alkaline by the addition of aqueous ammonia. The solution was used as the electrolyte solution for the production of metallic titanium according to my process.
- Example V To 300 cc. of a solution of titanium triethylate in ethyl alcohol (titanium content 17.94 grams/liter) 50 cc. of hydrazine hydrate (80%) were added and the solution was made alkaline with aqueous ammonia. The resultant solution was used as the electrolyte solution for the production of metallic titanium according to my process.
- Example VI To 300 cc. of a solution of titanium trihydroxide in commercial aqueous formaldehyde solution (titanium content 18.73 grams/liter) 50 cc. of hydrazine hydrate (80%) were added and the solution was made alkaline with aqueous ammonia. The resultant solution was used as the electrolyte solution for the production of metallic titanium according to my process.
- Example VII To 300 cc. of an alcoholic solution of titanium trifluoride (titanium content 19.67 grams/liter) 50 cc. of hydrazine hydrate (80%) were added and the solution was made alkaline with aqueous ammonia.
- Hydrogen ion concentration of the resultant solution was adjusted to a pH of 8 to 12, such that a sutficient reducing condition existed in the electrolyte solution for the electrolytic deposition of metallic titanium, and the solution was electrolyzed.
- a titanium deposit having a beautiful metallic luster was obtained on the cathode.
- Electrode material Anode carbon; cathode: pure copper plate.
- Rate-of titanium deposition 860 mg. per hour.
- An electrolytic process for the production of metallic titanium from aqueous solution of titanium compounds which comprises preparing an aqueous solution of a titanium compound in which titanium has a valency of three, converting the titanium compound into a titanium compound in which titanium has a valency of two by reduction, adjusting the aqueous solution of titanium compound in which titanium has a valency of two thus converted from the titanium compound in which titanium has a valency of three to alkaline condition so that reducing conditions exist in the solution, and subjecting the alkaline, aqueous solution to electrolysis while reducing conditions exist in the electrolyte solution during the electrolysis operation.
- An electrolytic process for the production of metallic titanium from aqueous solution of titanium compounds which comprises preparing an aqueous solution of titanium compound in which titanium has a valency of two, adjusting the pH of the aqueous solution of titanium compound to a suificiently alkaline value to bring the potential at which hydrogen is evolved and the potential at which titanium is deposited close to each other so that metallic titanium is deposited on the cathode while hydrogen is being evolved on it during the electrolysis and so that reducing conditions exist in the solution, and electrolyzing the so-adjusted aqueous solution of titanium compound in which titanium has a valency of two while reducing conditions exist in the electrolyte solution.
Description
United rates My invention relates to a process for the production of metallic titanium, and more particularly to an electrolytic process for the production of metallic titanium.
Metallic titanium is now produced by a dry method. There have been made many attempts to obtain metallic titanium by a wet method but none has succeeded. Thus, up to the present, production of metallic titanium by electrolysis of an aqueous solution of its compound has been considered as a very difiicult problem.
I have now devised a process to produce pure metallic titanium by electrolysis of an aqueous solution of titanium compounds economically at low cost. My novel process for the production of metallic titanium from an aqueous solution of titanium compounds comprises a water-soluble titanium compound in which titanium which has a valency of two or three is employed as the starting material. In the case where a titanium compound in which titanium has a valency of three is employed the compound is converted into a titanium compound in which titanium has a valency of two by reduction by means of a reducing metal or agent, or by electrolytic reduction, or by the combination of said two reduction methods, and the titanium compound in which titanium has a valency of two thus converted from a titanium compound in which titanium has a valency of three or a titanium compound in which titanium has a valency of two in itself is made alkaline such that a sufficient reducing condition will exist in the electrolyte solution during the electrolysis operation, and it is then electrolyzed.
As the starting material for my process water-soluble titanium in which titanium has a valency of two or three may be used. When a titanium compound in which the valency of titanium is three is employed, it is preferable to use such a titanium compound which can easily be converted into a titanium compound in which the valency of titanium is two, for example, halides, complex salts, etc.
When a titanium compound in which titanium has a valency of three is employed, the compound is converted into a titanium compound in which titanium has a valency of two by means of a reducing metal or agent or by electrolytic reduction or by the combination of said two reduction methods.
Titanium compounds in which titanium has a valency of three have the advantage that they are more stable and more easily obtainable. However, when a titanium compound in which titanium has a valency of three is employed, the compound must be converted into a titanium compound having a valency of two before electrolysis by employing a reducing metal or agent or by electrolytic reduction or by the combination of said two reduction methods. For example, the reduction can be accomplished by the use of sponge titanium, or formaldehyde, or hydrazine hydrate, or pyrogallic acid, or by combinations of two of these reducing agents. It may be also accomplished by electrolytic reduction either by itself or in combination with the use of one of the aforementioned reducing agents.
An aqueous solution of a water-soluble titanium compound in which titanium has a valency of two, which 3,074,860 Patented Jan. 22, 1963 may be a titanium compound in which titanium has a valency of two in itself, or a titanium compound in which titanium has a valency of two which has been converted from a titanium compound in which titanium has a valency of three, must be adjusted so as to be alkaline. The aqueous alkaline solution is then subjected to electrolysis. When the electrolysis is carried out with the solution alkaline such that a sufficient reducing condition exists in the electrolyte solution metallic titanium having a high purity is deposited on the cathode.
The reason why electrolytic production of metallic titanium which had been very difficult has been made possible by my process may be explained by the fact that, according to my process, a titanium compound in Which titanium has a valency of two is employed and a. suflicient reducing condition exists in the electrolyte solution during the electrolysis so that the oxidation of the titanium compound in which titanium has a valency of two in the electrolyte to a titanium compound inwhich titanium has a valency of three is prevented and, also, the oxidation of metallic titanium deposited on the cathode is prevented. The fact that the hydrogen ion concentration of the electrolyte solution is in the alkaline range produces the favorable result of bringing the potential at which hydrogen is evolved and the potential at which metallic titanium is deposited close to each other. By the combined ettects of above, pure metallic titanium is deposited on the cathode while hydrogen is being evolved on it. Thus, according to the process of my invention, metallic titanium is deposited on the cathode under similar conditions which prevail in the electrolytic production of manganese.
The process of my invention will be more clearly understood from the examples set forth below in which Examples I to VI illustrate the preparation of electrolyte solution of titanium compound in which titanium has a valency of two and Example VIE illustrates the elec-. trolysis operation. It will be understood that these examples are only for the purpose of illustration and my invention is in no way limited to the examples.
Example I An aqueous solution suitable for the electrolytic production of metallic titanium was prepared by dissolving 35 grams of titanium dichloride in 300 cc. of commercial aqueous formaldehyde solution, adding to the solution 10 grams of pyrogallic acid and then aqueous ammonia or caustic alkali to make the solution alkaline.
Example 11 To 300 cc. of an alcoholic solution of titanium trichloride were added 300 cc. of commercial aqueous formaldehyde solution and then 15 grams of pulverized sponge titanium. The mixture was heated at about 50 C. When the reduction was completed, the mixture was cooled and 10 grams of pyrogalli-c acid were added. Then, aqueous ammonia was added to make the solution alkaline. The resultant solution was used as the electrolyte solution for the production of metallic titanium according to my process.
Example 111 To 300 cc. of an aqueous solution of titanium borofluoride (titanium content 20.28 grams/liter) 50 cc. of thioglycollic acid were added and the resultant solution was electrolytically reduced using a carbon anode. When the reduction had proceeded to a point at which the solution turned to brown in color, the electrolysis was stopped. 10 grams of pyrogallic acid were added and then the solution was made alkaline by the addition of aqueous ammonia. The resultant solution was used as the electrolyte solution for the production of metallic titanium according to my process.
Example IV To 300 cc. of a solution of titanium trihydroxide in commercial aqueous formaldehyde solution (titanium content 18.73 grams/liter) grams of pyrogallic acid were added, and the resultant solution was subjected to the electrolytic reduction in the same manner as described in Example III. The resultant solution was made alkaline by the addition of aqueous ammonia. The solution was used as the electrolyte solution for the production of metallic titanium according to my process.
Example V To 300 cc. of a solution of titanium triethylate in ethyl alcohol (titanium content 17.94 grams/liter) 50 cc. of hydrazine hydrate (80%) were added and the solution was made alkaline with aqueous ammonia. The resultant solution was used as the electrolyte solution for the production of metallic titanium according to my process.
Example VI To 300 cc. of a solution of titanium trihydroxide in commercial aqueous formaldehyde solution (titanium content 18.73 grams/liter) 50 cc. of hydrazine hydrate (80%) were added and the solution was made alkaline with aqueous ammonia. The resultant solution was used as the electrolyte solution for the production of metallic titanium according to my process.
Example VII To 300 cc. of an alcoholic solution of titanium trifluoride (titanium content 19.67 grams/liter) 50 cc. of hydrazine hydrate (80%) were added and the solution was made alkaline with aqueous ammonia.
Hydrogen ion concentration of the resultant solution was adjusted to a pH of 8 to 12, such that a sutficient reducing condition existed in the electrolyte solution for the electrolytic deposition of metallic titanium, and the solution was electrolyzed. A titanium deposit having a beautiful metallic luster was obtained on the cathode.
Conditions of electrolysis employed were as follows:
Cell material Glass.
Volume of electrolyte solution" 2.5 liters.
Electrode material Anode: carbon; cathode: pure copper plate.
Current density 7 amp. per square decimeter.
Cell voltage 1.3 volts.
Distance between the electrodes- 85 mm.
Temperature of the electrolyte solution 18 C.
Conditions in the electroylte solution Always reducing. Rate-of titanium deposition 860 mg. per hour.
As will be seen from above, according to the process of my invention it is possible to obtain pure metallic titanium easily and economically. My process is particularly suitable for titanium plating since titanium of highest purity is deposited in a dense structure.
I claim:
1. .An electrolytic process for the production of metallic titanium from aqueous solution of titanium compounds which comprises preparing an alkaline, aqueous solution of a titanium compound in which titanium has a valency of two and in which reducing conditions exist, and subjecting the solution to electrolysis while reducing conditions exist in the electrolyte solution.
2. A process as described in claim 1 wherein the titanium compound is titanium dichloride.
3. An electrolytic process for the production of metallic titanium from aqueous solution of titanium compounds which comprises preparing an aqueous solution of a titanium compound in which titanium has a valency of three, converting the titanium compound into a titanium compound in which titanium has a valency of two by reduction, adjusting the aqueous solution of titanium compound in which titanium has a valency of two thus converted from the titanium compound in which titanium has a valency of three to alkaline condition so that reducing conditions exist in the solution, and subjecting the alkaline, aqueous solution to electrolysis while reducing conditions exist in the electrolyte solution during the electrolysis operation.
4. A process as described in claim 3 wherein the titinium compound in which titanium has a valency of three is reduced by means of pulverized, sponge titanium.
5. A process as described in claim 3 wherein the titanium compound in which titanium has a valency of three is reduced by means of formaldehyde.
6. A process as described in cailm 3 wherein the tanium compound in which titanium has a valency three is reduced by means of hydrazine hydrate.
7. A process as described in claim 3 wherein the tanium compound in which titanium has a valency three is reduced by means of pyrogallic acid.
8. A process as described in claim 3 wherein the tanium compound in which titanium has a valency of three is reduced by means of electrolytic reduction of an aqueous solution of the titanium compound to which a reducing acid has been added.
9. A process as described in claim 3 wherein the titanium compound in which titanium has a valency of three is titanium trifluoride.
10. A process as described in claim 3 wherein the titanium compound in which titanium has a valency of three is titanium borofluoride.
11. A process as described in claim 3 wherein the ti tanium compound in which titanium has a valency of three is titanium trihydroxide.
12. A process as described in claim 3 wherein the titanium compound in which titanium has a valency of three is titanium triethylate.
13. An electrolytic process for the production of metallic titanium from aqueous solution of titanium compounds which comprises preparing an aqueous solution of titanium compound in which titanium has a valency of two, adjusting the pH of the aqueous solution of titanium compound to a suificiently alkaline value to bring the potential at which hydrogen is evolved and the potential at which titanium is deposited close to each other so that metallic titanium is deposited on the cathode while hydrogen is being evolved on it during the electrolysis and so that reducing conditions exist in the solution, and electrolyzing the so-adjusted aqueous solution of titanium compound in which titanium has a valency of two while reducing conditions exist in the electrolyte solution.
14. A process as claimed in claim 3 in which the reduction is carried out by dissolving the trivalent titanium compound in an aqueous formaldehyde solution and then adding pyrogallic acid.
15. A process as claimed in claim 3 in which the reduction is carried out by dissolving the trivalent titanium compound in aqueous formaldehyde and then adding pulverized sponge titanium and heating the mixture.
16. A process as claimed in claim 3 in which the reduction is carried out by adding to an aqueous solution of the trivalent titanium compound thioglycollic acid, and then subjecting the resulting solution to electrolysis.
17. A process as claimed in claim 3 in which the reduction is carried out by adding to an aqueous solution of the trivalent titanium compound pyrogallic acid, and then subjecting the resulting solution to electrolysis.
18. The process as claimed in claim 3 in which the reduction is carried out by adding to an ethyl alcohol solution of the trivalent titanium compound hydrazine hydrate.
19. A process as claimed in claim 3 in which the retiof tiof 5 duction is carried out by adding hydrazine hydrate to a formaldehyde solution of the trivalent titanium compound.
References Cited in the file of this patent UNITED STATES PATENTS 1,113,546 Dekker Oct. 13, 1919 2,833,706 Wainer May 6, 1958 2,881,055 Dean Apr. 7, 1959 6 FOREIGN PATENTS OTHER REFERENCES Breton, E. J.: Electrodeposition of Titanium From Aqueous Systems, Wright Air Development Center Technical Report 52-232, Dayton, December 1952, pages 1-75.
Claims (1)
1. AN ELECTROLYTIC PROCESS FOR THE PRODUCTION OF METALLIC TITANIUM AQUEOUS SOLUTION OF TITANIUM COMPOUNDS WHICH COMPRISES PREPARING AN ALKALINE, AQUEOUS SOULTION OF A TITANIUM COMPOUND IN WHICH TITANIUM HAS A VALENCY IF TWO AND IN WHICH REDUCING CONDITION EXISTS, AND SUBJECTING THE SOULTION TO ELECTROLYSIS WHILE REDUCING CONDITIONS EXIST IN THE ELECTROLYTE SOULTION.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3074860X | 1959-01-16 |
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| Publication Number | Publication Date |
|---|---|
| US3074860A true US3074860A (en) | 1963-01-22 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US1455A Expired - Lifetime US3074860A (en) | 1959-01-16 | 1960-01-11 | Electrolytic process for the production of metallic titanium from aqueous solution of titanium compounds |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0023762A1 (en) * | 1979-06-27 | 1981-02-11 | Nihon Medel Company Limited | Method of plating with titanium and a substrate plated with titanium |
| KR101227059B1 (en) * | 2012-05-18 | 2013-01-28 | 윤종오 | Plating solution and method for zirconium alloy plating and titanium alloy plating |
| KR101227058B1 (en) * | 2012-10-22 | 2013-01-28 | 윤종오 | Titanium-zirconium alloy electroplating bath and method |
| KR101229500B1 (en) * | 2012-07-09 | 2013-02-04 | 이을규 | Titanium electroplating bath and method |
| KR101247938B1 (en) * | 2012-07-09 | 2013-04-02 | 윤종오 | Zirconium electroplating bath and method |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1113546A (en) * | 1912-08-17 | 1914-10-13 | Nicolas Henri Marie Dekker | Electrolyte for use in electrometallurgy. |
| US2833706A (en) * | 1956-05-16 | 1958-05-06 | Horizons Titanium Corp | Electrolytic method of producing titanium |
| US2881055A (en) * | 1956-08-20 | 1959-04-07 | Chicago Dev Corp | Control methods for fused baths |
-
1960
- 1960-01-11 US US1455A patent/US3074860A/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1113546A (en) * | 1912-08-17 | 1914-10-13 | Nicolas Henri Marie Dekker | Electrolyte for use in electrometallurgy. |
| US2833706A (en) * | 1956-05-16 | 1958-05-06 | Horizons Titanium Corp | Electrolytic method of producing titanium |
| US2881055A (en) * | 1956-08-20 | 1959-04-07 | Chicago Dev Corp | Control methods for fused baths |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0023762A1 (en) * | 1979-06-27 | 1981-02-11 | Nihon Medel Company Limited | Method of plating with titanium and a substrate plated with titanium |
| KR101227059B1 (en) * | 2012-05-18 | 2013-01-28 | 윤종오 | Plating solution and method for zirconium alloy plating and titanium alloy plating |
| KR101229500B1 (en) * | 2012-07-09 | 2013-02-04 | 이을규 | Titanium electroplating bath and method |
| KR101247938B1 (en) * | 2012-07-09 | 2013-04-02 | 윤종오 | Zirconium electroplating bath and method |
| KR101227058B1 (en) * | 2012-10-22 | 2013-01-28 | 윤종오 | Titanium-zirconium alloy electroplating bath and method |
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