Patent US4038364A successfully refreshed from Google Patents.
US4038364A
Expired / Lapsed
US
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Reduction of iron in titanium ore
Assignee: Bayer AG
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Filing: 1974-12-30
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Granted: 1977-07-26
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Expires: 1994-12-30
Abstract
Abstract In the production of synthetic rutile from a titanium and iron-containing ore by reducing most of the iron(III) in said ore into iron(II) with a steam-containing gaseous reducing agent at a temperature of about 850° to 1100° C, followed by leaching to remove the iron(II) and iron(III) and drying of the residue, the improvement which comprises using as said reducing agent a gas containing hydrogen and steam and optionally at least one of CO and CO 2 wherein the H 2 + CO : H 2 O + CO 2 molar ratio of the reducing agent is between 0.36 and 1.8. The reducing agent may comprise a mixture of hydrogen and steam or it may be the partial combustion product of a hydrocarbon. Advantageously, the ore is oxidized at 550° to 1200° C prior to reduction. The reduction permits ready dissolution of the iron during leaching without risk of hydrogen evolution.
Inventors
- 👤 Gunter Lailach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 14:37
CPC Classifications
C; C22; C22B; C22B34/00; C22B34/10; C22B34/12; C22B34/1204; C22B34/1209; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
119 words
In the production of synthetic rutile from a titanium and iron-containing ore by reducing most of the iron (III) in said ore into iron (II) with a steam-containing gaseous reducing agent at a temperature of about 850° to 1100° C., followed by leaching to remove the iron (II) and iron (III) and drying of the residue, the improvement which comprises using as said reducing agent hydrogen optionally containing CO, the gas in addition optionally containing CO 2 , the molar ratio of the H 2 + any CO present: H 2 O + any CO 2 present ranging between 0.36 and 1.8. whereby substantially no metallic iron is produced during reduction and substantially no hydrogen is produced during leaching.
Claim 2
Dependent Claim
119 words
In the production of synthetic rutile from a titanium and iron-containing ore by reducing most of the iron (III) in said ore into iron (II) with a steam-containing gaseous reducing agent at a temperature of about 850° to 1100° C., followed by leaching to remove the iron (II) and iron (III) and drying of the residue, the improvement which comprises using as said reducing agent hydrogen optionally containing CO, the gas in addition optionally containing CO 2 , the molar ratio of the H 2 + any CO present: H 2 O + any CO 2 present ranging between 0.36 and 1.8. whereby substantially no metallic iron is produced during reduction and substantially no hydrogen is produced during leaching.
Claim 3
Dependent Claim
21 words
A process as claimed in claim 1, wherein reduction is carried out at a temperature of about 950° to 1100° C.
Claim 4
Dependent Claim
32 words
A process as claimed in claim 1, wherein reduction is carried out with a mixture of hydrogen and steam at a H 2 :H 2 O molar ratio of 1.25 to 1.8.
Claim 5
Dependent Claim
45 words
A process as claimed in claim 1, wherein reduction is carried out with a partly burnt gaseous or liquid hydrocarbon containing hydrogen, steam, carbon monoxide and carbon dioxide at a H 2 + CO:H 2 O + CO 2 molar ratio of 0.65 to 1.5.
Claim 6
Dependent Claim
33 words
A process as claimed in claim 4, wherein the gaseous reducing agent is the product of burning the hydrocarbon with about 55 to 80% of the quantity of oxygen required for complete combustion.
Claim 7
Dependent Claim
15 words
A process as claimed in claim 5, wherein steam is additionally added during partial combustion.
Claim 8
Dependent Claim
20 words
A process as claimed in claim 1, wherein the gaseous reducing agent is mixed with at least one inert gas.
Claim 9
Dependent Claim
16 words
A process as claimed in claim 1, wherein the reduced ore is leached with mineral acid.
Claim 10
Dependent Claim
31 words
A process as claimed in claim 8, wherein the leaching agent is 17 to 22% by weight HCl and is used in about 130 to 170% of the stoichiometrically necessary quantity.
Claim 11
Dependent Claim
25 words
A process as claimed in claim 8, wherein leaching is carried out in a single stage over a period of about 2 to 5 hours.
Claim 12
Dependent Claim
20 words
A process as claimed in claim 8, wherein the solid leaching residue is calcined at about 750° to 1100° C.
Claim 13
Dependent Claim
56 words
A process as claimed in claim 2, wherein the reduced ore is leached in a single stage over a period of about 2 to 5 hours with 17 to 22% by weight HCl in about 150 to 160% of the stoichiometrically necessary quantity, and the solid leaching residue is calcined to about 800° to 850° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-25 | 1981-01-24 | 1981-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-25 | 1985-01-24 | 1985-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-25 | 1989-01-24 | 1989-07-26 | $7700.00 | Window Closed / Lapsed |