US3720756A
Expired / Lapsed
US
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Production of synthetic zeolites of faujasite structure
Assignee: Bayer AG
•
Filing: 1971-01-05
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Granted: 1973-03-13
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Expires: 1991-01-05
Abstract
Abstract A gel containing Na2O, Al2O3, SiO2 and H2O in the approximate molar ratios:
Inventors
- 👤 F Schwochow
- 👤 G Heinze
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:40
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/20; C01B33/26; C01B33/28; C01B33/2807; C01B33/2838; C01B33/2846; Y; Y10; Y10S; Y10S423/00; Y10S423/21
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
142 words
In the production of a synthetic zeolite wherein a sodium silicate solution and an aluminate solution are combined to form a gel containing Na2O, Al2O3, SiO2 and H2O, and the gel is hydrothermally crystallized, the improvement which comprises adjusting an aqueous solution of sodium silicate having the general formula Na2O. (2-4) SiO2 to an Na2O:SiO2 mole ratio of at least about 1.5:1 and an H2O:Na2O molE ratio of about 35-45:1, and maintaining said solution for at least about 1 hour before combining it with the aluminate solution, the compositions and proportions of the sodium silicate and aluminate solutions being such that the molar ratios in the gel are about: SiO2:Al2O3 3.5-5 Na2O:SiO2 2-3H2O :Na2O 35-45 and stirring the gel during hydrothermal crystallization whereby the product which crystallizes has the crystal structure of faujasite and a composition corresponding to the general formula Na2O.Al2O3.(2-2.5)SiO2.(0-8)H2O.
Claim 2
Dependent Claim
142 words
In the production of a synthetic zeolite wherein a sodium silicate solution and an aluminate solution are combined to form a gel containing Na2O, Al2O3, SiO2 and H2O, and the gel is hydrothermally crystallized, the improvement which comprises adjusting an aqueous solution of sodium silicate having the general formula Na2O. (2-4) SiO2 to an Na2O:SiO2 mole ratio of at least about 1.5:1 and an H2O:Na2O molE ratio of about 35-45:1, and maintaining said solution for at least about 1 hour before combining it with the aluminate solution, the compositions and proportions of the sodium silicate and aluminate solutions being such that the molar ratios in the gel are about: SiO2:Al2O3 3.5-5 Na2O:SiO2 2-3H2O :Na2O 35-45 and stirring the gel during hydrothermal crystallization whereby the product which crystallizes has the crystal structure of faujasite and a composition corresponding to the general formula Na2O.Al2O3.(2-2.5)SiO2.(0-8)H2O.
Claim 3
Dependent Claim
36 words
A process according to claim 1, wherein the sodium silicate solution is maintained at about 10* to 40* C. for about 1 to 4 hours after its adjustment and prior to combination with the aluminate solution.
Claim 4
Dependent Claim
20 words
A process according to claim 1, wherein hydrothermal crystallization of the gel is carried out substantially immediately after its formation.
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) | 1976-03-12 | 1976-09-11 | 1977-03-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-12 | 1980-09-11 | 1981-03-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-12 | 1984-09-11 | 1985-03-13 | $7700.00 | Window Closed / Lapsed |