EP0146909A2
Expired / Lapsed
EP
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Method of removing oxygen from a gas mixture containing oxygen and argon
Assignee: Air Products and Chemicals Inc
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Filing: 1984-12-18
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Granted: —
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Expires: 2004-12-18
Abstract
Abstract Molecular sieve carbons of tailored pore aperture size are prepared by sorbing a hydrocarbon, preferably propylene, in a degassed micropore-containing carbon substrate at an intermediate temperature, removing the physically held hydrocarbon while retaining at the pore apertures irreversibly fixed (chemisorbed or polymerized) hydrocarbon, and cracking the retained hydrocarbon at significantly higher temperature to deposit pyrocarbon at the pore apertures. To protect these molecular sieve carbons and other gas-sorbing carbons from loss of capacity and/or selectivity by exposure to moisture and/or oxygen, these carbons are treated with hydrogen at superatmospheric pressure.
Inventors
- 👤 Shyam K. Verma
- 👤 Philip L. Walker, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 13:55
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/20; B01D; B01D53/00; B01D53/02; C; C01; C01B; C01B13/00; C01B13/02; C01B13/0229; C01B13/0248; C01B13/0259; C01B13/0262; C01B13/0266; C01B23/00; C01B32/00; C01B32/30; C01B32/306; C01B2210/00; C01B2210/0043; C01B2210/0078
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
108 words
the method of preparing molecular sieve carbons having pore apertures of controlled size range, which comprises initially degassing a micropore-containing carbon substrate at an elevated temperature, cooling the degassed carbon substrate to an intermediate temperature in the range of 300 to 500°C and exposing the cooled carbon at said temperature to contact with a hydrocarbon in vapor form to sorb said hydrocarbon therein, removing physically held hydrocarbon from said carbon substrate by degassing the same under vacuum and at about said exposing temperature, thereafter cracking remaining hydrocarbon fixedly held at the pore apertures of said substrate at a higher temperature thereby depositing pyrocarbon at the said pore apertures.
Claim 2
Independent Claim
108 words
the method of preparing molecular sieve carbons having pore apertures of controlled size range, which comprises initially degassing a micropore-containing carbon substrate at an elevated temperature, cooling the degassed carbon substrate to an intermediate temperature in the range of 300 to 500°C and exposing the cooled carbon at said temperature to contact with a hydrocarbon in vapor form to sorb said hydrocarbon therein, removing physically held hydrocarbon from said carbon substrate by degassing the same under vacuum and at about said exposing temperature, thereafter cracking remaining hydrocarbon fixedly held at the pore apertures of said substrate at a higher temperature thereby depositing pyrocarbon at the said pore apertures.
Claim 3
Dependent Claim
22 words
The method as defined in Claim 1 wherein said initial degassing is carried out at a temperature in the range of 800-900°C.
Claim 4
Dependent Claim
20 words
The method as defined in Claim 2 wherein said cracking is effected at a temperature in the range of 800-900°C.
Claim 5
Dependent Claim
27 words
The method as defined in Claim 1 wherein said starting carbon substrate is one having a pore size in the range of about 0.5 to 0.55 nm.
Claim 6
Dependent Claim
13 words
The method as defined in Claim 4 wherein said sorbed hydrocarbon comprises propylene.
Claim 7
Dependent Claim
28 words
The method as defined in Claim 5 wherein said cracking is effected at a temperature in the range of 800-900°C while positively withdrawing gaseous products of said cracking.
Claim 8
Dependent Claim
44 words
The method as defined in Claim 1 wherein said carbon substrate containing deposited pyrocarbon is passivated by treatment with hydrogen under superatmospheric pressure to protect the same against loss of gas-sorption capacity and/or selectivity on , exposure to an environment comprising moisture and/or oxygen.
Claim 9
Dependent Claim
24 words
The method as defined in Claim 7 wherein said hydrogen treatment is carried out at a temperature in the range of 100 to 200°C.
Claim 10
Independent Claim
42 words
The method of passivating gas-sorbing carbon against loss of sorption capacity and/or selectivity by exposure to moisture and/or oxygen, which comprises subjecting said carbon to treatment with hydrogen at superatmospheric pressure and at a temperature in the range of 100 to 200°C.
Claim 11
Independent Claim
42 words
The method of passivating gas-sorbing carbon against loss of sorption capacity and/or selectivity by exposure to moisture and/or oxygen, which comprises subjecting said carbon to treatment with hydrogen at superatmospheric pressure and at a temperature in the range of 100 to 200°C.
Claim 12
Dependent Claim
53 words
The method of removing oxygen from a gas mixture containing oxygen and argon which comprises subjecting such gas mixture to selective oxygen adsorption by a mclecular sieve carbon produced by the process of Claim 1 said carbon sieve having a controlled pore aptrture diameter greater than 0.280 nm but less than 0.384 nm.
References Cited (Backward Citations)
No citation records indexed.
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