Claims
- 1. A process for separating a feed gas into at least one product gas, said process comprising:providing a gas separation apparatus comprising at least one adsorption layer comprising a lithium-exchanged FAU adsorbent having water desorption characteristics, defined by drying curves, similar to those for the corresponding fully sodium-exchanged FAU, and having a heat of adsorption for carbon dioxide equal to or lower than that for the corresponding fully sodium-exchanged FAU at high loadings of carbon dioxide, wherein said lithium-exchanged FAU adsorbent contains less than 0.01% calcium and less than 0.01% magnesium; feeding into said gas separation apparatus said feed gas comprising nitrogen, oxygen, and at least one of carbon dioxide and water; adsorbing water and/or carbon dioxide onto said at least one adsorption layer; and collecting from said gas separation apparatus said at least one product gas comprising oxygen.
- 2. The process of claim 1, wherein said FAU adsorbent has a Si/Al ratio between 1.0 and 1.3.
- 3. The process of claim 2, wherein said adsorbent has a lithium exchange level of more than 67%.
- 4. The process of claim 3, wherein said adsorbent is LiLSX.
- 5. The process of claim 3, wherein said adsorbent is LiMLSX, wherein M represents one or more elements selected from alkaline, alkaline-earth, transition metals and rare-earth groups.
- 6. The process of claim 1, wherein said at least one product gas contains at least 85% oxygen.
- 7. The process of claim 1, wherein said gas separation apparatus has a radial flow bed configuration.
- 8. The process of claim 1, wherein said gas separation apparatus has a cross flow configuration.
- 9. The process of claim 1, wherein said process comprises adsorbing water from said feed gas onto said at least one adsorption layer, and a productivity of said process for producing said product gas diminishes as a function of an amount of water adsorbed more slowly than a reference productivity of a reference process identical to said process but for use of a lithium-exchanged FAU adsorbent containing at least 0.01% calcium and/or at least 0.01% magnesium.
- 10. The process of claim 9, wherein the feed gas has a relative humidity greater than 70%.
CROSS-REFERENCE TO RELATED APPLICATIONS
This is a continuation in part to U.S. application Ser. No. 09/707,317 filed Nov. 7, 2000 now abandoned.
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Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
09/707317 |
Nov 2000 |
US |
Child |
10/341663 |
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US |