US4534947A
Expired / Lapsed
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Process for direct synthesis of sodium- and potassium-containing zeolite A
Assignee: ExxonMobil Technology and Engineering Co
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Filing: 1984-05-04
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Granted: 1985-08-13
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Expires: 2004-05-04
Abstract
Abstract Zeolite A containing sodium and potassium ions, otherwise known as 3 ANGSTROM molecular sieve, may be prepared by a direct route when the aqueous aluminosilicate reaction mixture to be aged at elevated temperatures contains a mole ratio of Na2O to Na2O and K2O which is greater by a factor of about 1.1 than the mole ratio of Na2O to Na2O and K2O in the zeolite A product. Preferably, the reaction mixture also contains zeolitic nucleation seeds to promote crystallization of the product.
Inventors
- 👤 David E. W. Vaughan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:47
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/20; C01B33/26; C01B33/28; C01B33/2807; C01B33/2815; Y; Y10; Y10S; Y10S423/00; Y10S423/24
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
149 words
A process for directly preparing a Type 3A zeolite containing sodium and potassium ions comprising the steps of: (a) preparing a reaction mixture comprising sodium silicate, potassium silicate, water, a source of alumina, and adding a seed source, said seed source comprising Type A zeolites, and the reaction mixture having a composition, expressed in mole ratios of oxides, within the ranges: (Na 2 O+K 2 O):Al 2 O 3 --1.4 to 2.1 SiO 2 :Al 2 O 3 --1.8 to 2.5 H 2 O:Al 2 O 3 --40 to 100 Na 2 O:Al 2 O 3 --0.3 to 1.0 K 2 O:Al 2 O 3 --1.3 to 1.7 (b) maintaining the reaction mixture at a temperature of between about 60° and 120° C. for a time sufficient to form a substantially pure crystalline zeolite 3A product, and (c) recovering a substantially pure Type 3A zeolite from the reaction mixture.
Claim 2
Dependent Claim
149 words
A process for directly preparing a Type 3A zeolite containing sodium and potassium ions comprising the steps of: (a) preparing a reaction mixture comprising sodium silicate, potassium silicate, water, a source of alumina, and adding a seed source, said seed source comprising Type A zeolites, and the reaction mixture having a composition, expressed in mole ratios of oxides, within the ranges: (Na 2 O+K 2 O):Al 2 O 3 --1.4 to 2.1 SiO 2 :Al 2 O 3 --1.8 to 2.5 H 2 O:Al 2 O 3 --40 to 100 Na 2 O:Al 2 O 3 --0.3 to 1.0 K 2 O:Al 2 O 3 --1.3 to 1.7 (b) maintaining the reaction mixture at a temperature of between about 60° and 120° C. for a time sufficient to form a substantially pure crystalline zeolite 3A product, and (c) recovering a substantially pure Type 3A zeolite from the reaction mixture.
Claim 3
Dependent Claim
29 words
The process of claim 1 wherein the seed source is present in the reaction mixture in an effective amount of up to 20% by weight of the reaction mixture.
Claim 4
Dependent Claim
25 words
The process of claim 1 wherein after step (a) but before step (b) the reaction mixture is blended sufficiently to form a substantially homogeneous mixture.
Claim 5
Dependent Claim
24 words
The process of claim 1 wherein the reaction mixture is maintained at a temperature of 80° to 100° C. for up to 24 hours.
Claim 6
Dependent Claim
57 words
The process of claim 1 wherein the reaction mixture has a composition, expressed in mole ratios of oxides, within the ranges: Na 2 O:Al 2 O 3 --0.3 to 1.0 K 2 O:Al 2 O 3 --1.3 to 1.7 SiO 2 :Al 2 O 3 --1.9 to 2.2 H 2 O:Al 2 O 3 --50 to 80.
Claim 7
Dependent Claim
16 words
The process of claim 2 wherein the zeolite product has a K/Na ratio greater than unity.
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) | 1988-08-12 | 1989-02-11 | 1989-08-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-12 | 1993-02-11 | 1993-08-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-12 | 1997-02-11 | 1997-08-13 | $7700.00 | Window Closed / Lapsed |