US3899310A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alumina-zeolite composite adsorbents for refrigerants
Assignee: WR Grace and Co
•
Filing: 1974-03-20
•
Granted: 1975-08-12
•
Expires: 1994-03-20
Abstract
Abstract A composite alumina-zeolite adsorbent exhibits synergistic properties for the adsorption of fatty acid compounds from refrigerant gases. A composite adsorbent takes up about 30 mg. of fatty acid per gram of adsorbent, while alumina takes up about 21 mg. of fatty acid and zeolites about 9 mg. of fatty acid per gram of adsorbent. A simple comixture would be expected to take up in the range of 9 to 21 mg. of fatty acid, depending on the composition, but the alumina-zeolite composite adsorbents will instead take up about 30 mg. It has also been found that aluminazeolite composites can be substantially strengthened by a moisture treatment.
Inventors
- 👤 Donald G Chi
- 👤 Hanju Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 02:51
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/16; B01J20/18; B01J20/183; B01D; B01D53/00; B01D53/02
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
56 words
A METHOD FOR REMOVING FATTY ACID CONTAMINANTS FROM A HALOCARBON REFRIGERANT GAS COMPRISING CONTACTING SAID GAS WITH A COMPOSITE ALUMINA-ZEOLITE ADSORBENT FORMED FROM BLENDED ZEOLITE AND ALUMINA POWDERS, SAID ZEOLITE COMPONENT HAVING A PORE DIAMETER OF 3 TO 6 ANGSTROMS AND COMPRISING 20 TO 80 PERCENT BY WEIGHT OF SAID COMPOSITE AND THE REMAINDER BEING ALUMINA.
Claim 2
Independent Claim
56 words
A METHOD FOR REMOVING FATTY ACID CONTAMINANTS FROM A HALOCARBON REFRIGERANT GAS COMPRISING CONTACTING SAID GAS WITH A COMPOSITE ALUMINA-ZEOLITE ADSORBENT FORMED FROM BLENDED ZEOLITE AND ALUMINA POWDERS, SAID ZEOLITE COMPONENT HAVING A PORE DIAMETER OF 3 TO 6 ANGSTROMS AND COMPRISING 20 TO 80 PERCENT BY WEIGHT OF SAID COMPOSITE AND THE REMAINDER BEING ALUMINA.
Claim 3
Dependent Claim
27 words
A method as in claim 1 wherein said composite contains about 30 to 65 percent by weight of said zeolite component and said halocarbon is a fluocarbon.
Claim 4
Dependent Claim
19 words
A method as in claim 2 wherein said composite contains about 50 percent by weight of said zeolite component.
Claim 5
Dependent Claim
40 words
A method as in claim 1 wherein said fatty acid contaminant is oleic acid and said refrigerant gas is selected from the group consisting of dichlorodifluoromethane, chlorodifluoromethane, trichlorofluoromethane, chlorotrifluoromethane, dichlorofluoromethane, trifluoromethane, trichlorotrifluoroethane, dichlorotetrafluoroethane, dibromotetrafluoroethane, chloropentofluoroethane, hexafluoroethane and other fluorocarbon compounds.
Claim 6
Dependent Claim
26 words
A method as in claim 1 wherein said zeolite component is a member selected from the group consisting of zeolite 3A, zeolite 4A and zeolite 5A.
Claim 7
Dependent Claim
27 words
A method as in claim 5 wherein said composite contains about 30 to 65 percent by weight of said zeolite component and said halocarbon is a fluocarbon.
Claim 8
Dependent Claim
41 words
A method as in claim 6 wherein said fatty acid contaminant is oleic acid and said refrigerant gas is selected from the group consisting of dichlorodifluoromethane, chlorodifluoromethane, trichlorofluoromethane, chlorotrifluoromethane, tetrafluoromethane, dichlorofluoromethane, trifluoromethane, trichlorotrifluoroethane, dichlorotetrafluoroethane, dibromotetrafluoroethane, chloropentofluoroethane, hexafluoroethane and other fluorocarbon compounds.
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) | 1978-08-11 | 1979-02-10 | 1979-08-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-08-11 | 1983-02-10 | 1983-08-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-08-11 | 1987-02-10 | 1987-08-12 | $7700.00 | Window Closed / Lapsed |