US4125591A
Expired / Lapsed
US
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Process for producing rare earth exchanged crystalline aluminosilicate
Assignee: Wyeth Holdings LLC
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Filing: 1973-12-13
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Granted: 1978-11-14
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Expires: 1993-12-13
Abstract
Abstract A process for preparing rare earth exchanged zeolite X and zeolite Y having improved activity and stability. The process of this invention involves partially exchanging sodium forms of zeolite X and zeolite Y with a solution of rare earth ions; calcining the partially exchanged zeolites; and further exchanging the calcined partially exchanged zeolites to replace remaining alkali metal ions.
Inventors
- 👤 John F. Lindsley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:36
CPC Classifications
B; B01; B01J; B01J29/00; B01J29/04; B01J29/06; B01J29/08; Y; Y10; Y10S; Y10S423/00; Y10S423/21
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
143 words
A process for producing rare earth exchange zeolite Y of improved activity and stability which comprises treating an aqueous solution of rare earth metal salt wherein the cations consist essentially of rare earth metal cations so as to obtain a partial exchange of alkali metal cations by rare earth metal cations such that the alkali metal content of zeolite Y is in the range of 3 to 4%, said percentage based on the dry weight of zeolite; calcining the resultant partially exchanged zeolite by heating the same to a temperature above about 450° C. to provide a dehydrated zeolite characterized by the same spatial relationship and unit cell size as the zeolite prior to calcination and treating the resultant calcined partially exchanged zeolite with a second aqueous solution containing rare earth metal cations to reduce further the alkali metal content of said zeolite.
Claim 2
Dependent Claim
143 words
A process for producing rare earth exchange zeolite Y of improved activity and stability which comprises treating an aqueous solution of rare earth metal salt wherein the cations consist essentially of rare earth metal cations so as to obtain a partial exchange of alkali metal cations by rare earth metal cations such that the alkali metal content of zeolite Y is in the range of 3 to 4%, said percentage based on the dry weight of zeolite; calcining the resultant partially exchanged zeolite by heating the same to a temperature above about 450° C. to provide a dehydrated zeolite characterized by the same spatial relationship and unit cell size as the zeolite prior to calcination and treating the resultant calcined partially exchanged zeolite with a second aqueous solution containing rare earth metal cations to reduce further the alkali metal content of said zeolite.
Claim 3
Dependent Claim
30 words
The process of claim 1 wherein a rare earth exchanged zeolite Y having a rare earth metal oxide content of about 18.5% by weight on a dry basis is obtained.
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) | 1981-11-13 | 1982-05-15 | 1982-11-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-11-13 | 1986-05-15 | 1986-11-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-11-13 | 1990-05-15 | 1990-11-14 | $7700.00 | Window Closed / Lapsed |