US4036940A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recovery of iodine
Assignee: Monsanto Co
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Filing: 1975-12-29
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Granted: 1977-07-19
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Expires: 1995-12-29
Abstract
Abstract Iodine is recovered from a process stream containing it or iodine-containing compounds by passing said stream while in the vapor state in contact with a solid treating agent or adsorbent comprising alumina impregnated with the oxides of copper and chromium and thereafter subjecting said solid treating agent to heating to a temperature from about 400 DEG to about 600 DEG C while passing a stream containing air or oxygen over it. The resulting effluent gas containing iodine can be fed directly back to the process from which it was derived or otherwise treated as by sublimation, for example, if desired.
Inventors
- 👤 Martin M. McLane
- 👤 Raymond A. Newsom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 02:33
CPC Classifications
B; B01; B01D; B01D53/00; B01D53/34; B01D53/46; B01D53/68; B01D53/74; B01D53/86; B01D53/8659; C; C01; C01B; C01B7/00; C01B7/13; C01B7/14; C07; C07C; C07C51/00; C07C51/42; C07C51/47
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
136 words
A process for recovery of iodine from a process stream containing iodine or iodine-containing reaction products and a reducing agent which comprises passing said stream while in the vapor state in contact with a treating agent comprising alumina impregnated with the oxides of copper and chromium wherein the amount of copper oxide is from about 5 to about 25 wt.% as Cu and the amount of chromium oxide is from about 1 to about 5 wt.% as chromium, said contacting being effected at a temperature from about 300° to about 500° C., and thereafter regenerating said treating agent by heating it while passing oxygen, air, oxygen -- inert gas or air -- inert gas mixtures therethrough at a temperature from about 400° to about 600° C. for a period from about 1 to about 12 hours.
Claim 2
Dependent Claim
136 words
A process for recovery of iodine from a process stream containing iodine or iodine-containing reaction products and a reducing agent which comprises passing said stream while in the vapor state in contact with a treating agent comprising alumina impregnated with the oxides of copper and chromium wherein the amount of copper oxide is from about 5 to about 25 wt.% as Cu and the amount of chromium oxide is from about 1 to about 5 wt.% as chromium, said contacting being effected at a temperature from about 300° to about 500° C., and thereafter regenerating said treating agent by heating it while passing oxygen, air, oxygen -- inert gas or air -- inert gas mixtures therethrough at a temperature from about 400° to about 600° C. for a period from about 1 to about 12 hours.
Claim 3
Dependent Claim
10 words
The process of claim 1 wherein said alumina is alpha-alumina.
Claim 4
Dependent Claim
39 words
The process of claim 2 wherein the amount of copper oxide is from about 5% to about 10% by weight as Cu and the amount of chromium oxide is from about 1 to about 2% by weight as Cr.
Claim 5
Dependent Claim
22 words
The process of claim 3 wherein said regeneration is effected by heating over a period of from about 4 about 8 hours.
Claim 6
Dependent Claim
153 words
A process for recovery of iodine from a process stream containing iodine or iodine-containing reaction products which comprises passing said stream while in the vapor state at a temperature from about 300° to about 500° C. in contact with a treating agent comprising alumina impregnated with the oxides of copper and chromium wherein the amount of copper oxide is from about 5 to about 25 wt.% as Cu and the amount of chromium oxide is from about 1 to about 2 wt.% as chromium, said treating agent having been subjected prior to use to treatment with a reducing agent to reduce the metal oxides present to their elemental forms, and thereafter regenerating said treating agent by heating it while passing oxygen, air, oxygen -- inert gas or air -- inert gas mixtures therethrough at a temperature from about 400° to about 600° C. for a period from about 1 to about 12 hours.
Claim 7
Dependent Claim
153 words
A process for recovery of iodine from a process stream containing iodine or iodine-containing reaction products which comprises passing said stream while in the vapor state at a temperature from about 300° to about 500° C. in contact with a treating agent comprising alumina impregnated with the oxides of copper and chromium wherein the amount of copper oxide is from about 5 to about 25 wt.% as Cu and the amount of chromium oxide is from about 1 to about 2 wt.% as chromium, said treating agent having been subjected prior to use to treatment with a reducing agent to reduce the metal oxides present to their elemental forms, and thereafter regenerating said treating agent by heating it while passing oxygen, air, oxygen -- inert gas or air -- inert gas mixtures therethrough at a temperature from about 400° to about 600° C. for a period from about 1 to about 12 hours.
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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) | 1980-07-18 | 1981-01-17 | 1981-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-18 | 1985-01-17 | 1985-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-18 | 1989-01-17 | 1989-07-19 | $7700.00 | Window Closed / Lapsed |