US3926615A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pretreatment of titanium-iron ores
Assignee: Bayer AG
•
Filing: 1973-07-09
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Granted: 1975-12-16
•
Expires: 1993-07-09
Abstract
Abstract In the production of a titanium dioxide concentrate from a titanium-iron ore wherein the ore is oxidized in a pretreatment, thereafter reduced to form metallic iron in association with titanium dioxide or activated ilmenite and thereafter leached to remove iron and leave a titanium dioxide concentrate, the improvement which comprises effecting the oxidation by first forming unhardened agglomerates of the titanium-iron ore, heating the unhardened agglomerates to a temperature of up to about 900*C, at least the heating from about 600* to 900*C being effected under non-oxidizing conditions, and thereafter heating said agglomerates at a temperature in the range of about 900* to 1200*C under oxidizing conditions until substantially all the iron has been converted into a ferro pseudobrookitepseudobrookite mixed phase. Preferably, the oxidation is carried out with a flue gas containing about 7 to 13 volume percent of oxygen and more than 0.1 volume percent of water at a temperature of about 950* to 1100*C, oxidation being continued until the ratio of trivalent iron to total iron is at least about
Inventors
- 👤 Gunter Lailach
- 👤 Jakob Rademachers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:58
CPC Classifications
C; C22; C22B; C22B34/00; C22B34/10; C22B34/12; C22B34/1204; C22B34/1209
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
131 words
IN THE PRODUCTION OF A TITANIUM DIOXIDE CONCENTRATE FROM A TITANIUM-IRON ORE WHEREIN THE ORE IS OXIDIZED IN A PRETREATMENT, THEREAFTER REDUCED TO FORM A METALLIC IRON IN ASSOCIATION WITH TITANIUM DIOXIDE OR ACTIVATED ILMENITE AND THEREAFTER LEACHED TO REMOVE IRON AND LEAVE A TITANIUM DIOXIDE CONCENTRATE, THE IMPROVEMENT WHICH COMPRISES FIRST FORMING UNHARDENED AGGLOMERATES OF THE TITANIUM-IRON ORE, HEATING THE UNHARDENDED AGGLOMERATES TO A TEMPERATURE OF UP TO ABOUT 900*C, AT LEAST THE HEATING FROM ABOUT 600* TO 900*C BEING EFFECTED UNDER NON-OXIDIZING CONDITIONS THEREBY TO AVIOD FORMATION OF HEMATITE, AND THEREAFTER EFFECTING SAID OXIDATION OF THE ORE BY HEATING SAID AGGLOMERATES AT A TEMPEATURE IN THE RANGE OF ABOUT 900* TO 1200*C UNDER OXIDIZING CONDITIONS UNTIL SUBSTANTIALLY ALL THE IRON HAS BEEN CONVERTED INTO A FERRO PSEUDOBROOKITEPSEUDOBROOKITE MIXED PHASE.
Claim 2
Dependent Claim
131 words
IN THE PRODUCTION OF A TITANIUM DIOXIDE CONCENTRATE FROM A TITANIUM-IRON ORE WHEREIN THE ORE IS OXIDIZED IN A PRETREATMENT, THEREAFTER REDUCED TO FORM A METALLIC IRON IN ASSOCIATION WITH TITANIUM DIOXIDE OR ACTIVATED ILMENITE AND THEREAFTER LEACHED TO REMOVE IRON AND LEAVE A TITANIUM DIOXIDE CONCENTRATE, THE IMPROVEMENT WHICH COMPRISES FIRST FORMING UNHARDENED AGGLOMERATES OF THE TITANIUM-IRON ORE, HEATING THE UNHARDENDED AGGLOMERATES TO A TEMPERATURE OF UP TO ABOUT 900*C, AT LEAST THE HEATING FROM ABOUT 600* TO 900*C BEING EFFECTED UNDER NON-OXIDIZING CONDITIONS THEREBY TO AVIOD FORMATION OF HEMATITE, AND THEREAFTER EFFECTING SAID OXIDATION OF THE ORE BY HEATING SAID AGGLOMERATES AT A TEMPEATURE IN THE RANGE OF ABOUT 900* TO 1200*C UNDER OXIDIZING CONDITIONS UNTIL SUBSTANTIALLY ALL THE IRON HAS BEEN CONVERTED INTO A FERRO PSEUDOBROOKITEPSEUDOBROOKITE MIXED PHASE.
Claim 3
Dependent Claim
16 words
The process according to claim 1, wherein the oxidation is carried out with an oxygen-containing gas.
Claim 4
Dependent Claim
25 words
The process according to claim 2, wherein the oxidation is carried out with a flue gas containing about 7 to 13 volume percent of oxygen.
Claim 5
Dependent Claim
23 words
The process according to claim 1, wherein the oxidation is carried out in the presence of more than 0.1 volume percent of water.
Claim 6
Dependent Claim
20 words
The process according to claim 1 wherein the oxidation is carried out at a temperature of about 950* to 1100*C.
Claim 7
Dependent Claim
24 words
The process according to claim 1, wherein the oxidation is continued until the ratio of trivalent iron to total iron is at least about
Claim 8
Dependent Claim
48 words
The process according to claim 1, wherein the unhardened titanium-iron ore agglomerates are hardened, and thereafter preheated to 900*C in admixture with about 0.5 to 10 percent by weight of carbon-containing material while in contact with an oxygencontaining gas, whereby the carbon ensures that the atmosphere is non-oxidizing.
Claim 9
Dependent Claim
21 words
The process according to claim 7 wherein the carbon is consumed and oxidation is thereafter effected with a hot oxygen-containing gas.
Claim 10
Dependent Claim
28 words
The process according to claim 1 wherein the titanium-iron ore agglomerates in addition to titanium-iron ore contain at least one of iron compounds, titanium compounds and carbon-containing material.
Claim 11
Dependent Claim
57 words
The process according to claim 9, wherein the oxidation is carried out with a flue gas containing about 7 to 13 volume percent of oxygen and more than 0.1 volume percent of water at a temperature of about 950* to 1100*C, oxidation being continued until the ratio of trivalent iron to total iron is at least about
Claim 12
Dependent Claim
32 words
The process according to claim 1 wherein the agglomerates are placed on a carrier and successively carried through zones in which they are hardened, preheated in a non-oxidizing atmosphere, and then oxidized.
Claim 13
Dependent Claim
11 words
The process according to claim 1, wherein the ore contains pseudobrookite.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-12-15 | 1979-06-16 | 1979-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-15 | 1983-06-16 | 1983-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-15 | 1987-06-16 | 1987-12-16 | $7700.00 | Window Closed / Lapsed |