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US4120694A
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Process for purifying a titanium-bearing material and upgrading ilmenite to synthetic rutile with sulfur trioxide
Assignee: United States Department of the Interior
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Filing: 1977-09-06
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Granted: 1978-10-17
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Expires: 1997-09-06
Abstract
Abstract A process for removing impurities from an oxide of titanium-bearing material such as a titania slag by treating the material with SO3 gas and subsequently leaching with a liquid. In particular a process for upgrading an ilmenite ore by preparing a titania slag therefrom and purifying the slag such that it may be used as a synthetic rutile suitable for use in a fluidized-bed chlorination reactor to produce titanium tetrachloride which can be reoxidized to TiO2.
Inventors
- 👤 Gerald W. Elger
- 👤 Ruth A. Stadler
- 👤 Philip E. Sanker
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:48
CPC Classifications
C; C22; C22B; C22B34/00; C22B34/10; C22B34/12; C22B34/1218; C22B34/1222; C22B34/1204; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
51 words
A process for removing alkaline earth oxide impurities from a titania slag consisting essentially of reacting said slag with sulfur trioxide gas at a temperature of about 600° to 1100° C to form a reaction product containing alkaline earth sulfates, and subsequently leaching said sulfates from the reaction product with water.
Claim 2
Dependent Claim
51 words
A process for removing alkaline earth oxide impurities from a titania slag consisting essentially of reacting said slag with sulfur trioxide gas at a temperature of about 600° to 1100° C to form a reaction product containing alkaline earth sulfates, and subsequently leaching said sulfates from the reaction product with water.
Claim 3
Dependent Claim
19 words
The process of claim 1, wherein said slag comprises a titanium slag produced by the smelting of ilmenite ore.
Claim 4
Dependent Claim
18 words
The process of claim 2, wherein said ilmenite ore comprises about 45 to 65% by weight titanium dioxide.
Claim 5
Dependent Claim
14 words
The process of claim 1, wherein said impurities comprise calcium oxide and magnesium oxide.
Claim 6
Dependent Claim
26 words
The process of claim 1, wherein said reacting comprises the reaction of sulfur trioxide with at least one alkaline earth oxide to produce the corresponding sulfate.
Claim 7
Dependent Claim
27 words
The process of claim 1, wherein said reacting is in the presence of gaseous oxygen resulting in the conversion of lower valence titanium oxides to titanium dioxide.
Claim 8
Dependent Claim
55 words
A process for upgrading ilmenite ore to a synthethic rutile ore comprising the steps of: a. producing a titania slag containing alkaline earth impurities from ilmenite ore; b. reacting said titania slag with sulfur trioxide gas at 600° to 1100° C; and subsequently c. leaching said alkaline earth impurities from the titania slag with water.
Claim 9
Dependent Claim
55 words
A process for upgrading ilmenite ore to a synthethic rutile ore comprising the steps of: a. producing a titania slag containing alkaline earth impurities from ilmenite ore; b. reacting said titania slag with sulfur trioxide gas at 600° to 1100° C; and subsequently c. leaching said alkaline earth impurities from the titania slag with water.
Claim 10
Dependent Claim
18 words
The process of claim 7, wherein step a) comprises smelting ilmenite ore to produce a titania slag fraction.
Claim 11
Dependent Claim
18 words
The process of claim 8, wherein said ilmenite ore comprises about 45 to 65% by weight titanium dioxide.
Claim 12
Dependent Claim
24 words
The process of claim 7, wherein in step c), at least one alkaline earth sulfate is removed from the titania slag by said leaching.
Claim 13
Dependent Claim
23 words
The process of claim 10, wherein said at least one alkaline earth sulfate comprises the double sulfate CaSO 4 . 3MgSO 4 .
Claim 14
Dependent Claim
29 words
The process of claim 7, wherein in step (b), said reaction comprises the reaction of sulfur trioxide with at least one alkaline earth oxide to produce the corresponding sulfate.
Claim 15
Dependent Claim
27 words
The process of claim 7, wherein said reacting is in the presence of gaseous oxygen resulting in the conversion of lower valence titanium oxides to titanium dioxide.
References Cited (Backward Citations)
US1819770A
Cited
US1820455A
Cited
US1964747A
Cited
US2098050A
Cited
US2818347A
Cited
US2804384A
Cited
US2919982A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-10-16 | 1982-04-17 | 1982-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-10-16 | 1986-04-17 | 1986-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-10-16 | 1990-04-17 | 1990-10-17 | $7700.00 | Window Closed / Lapsed |