US4166099A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Preparation of zeolites
Assignee: WR Grace and Co Conn
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Filing: 1977-06-02
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Granted: 1979-08-28
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Expires: 1997-06-02
Abstract
Abstract Crystalline alluminosilicate zeolites are rapidly and efficiently prepared by seeding an aqueous mixture containing alumina, silica, and alkali metal hydroxide with zeolite seeds, i.e. nucleation centers having an average size below about 0.1 micron.
Inventors
- 👤 Carl V. McDaniel
- 👤 Phillip K. Maher
- 👤 Joseph M. Pilato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 12:40
CPC Classifications
C; C01; C01B; C01B39/00; C01B39/02; C01B39/20; Y; Y10; Y10S; Y10S423/00; Y10S423/21
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
201 words
A method for preparing a crystalline aluminosilicate zeolite which comprises: (a) Preparing an aqueous precursor mixture of silica, alumina and alkali metal hydroxide, the proportions of said silica, alumina and alkali metal hydroxide being those required to produce the desired zeolite; (b) Adding to said precursor mixture from about 0.1 to about 10 percent by weight based on the weight of the theoretical yield of desired zeolite of amorphous aluminosilicate nucleation centers having the molar composition 0.9±0.1 Na 2 O:Al 2 O 3 :2.3-2.7 SiO 2 having an average particle size below 0.1 micron prepared by a process which comprises: (i) preparing an Na 2 O-Al 2 O 3 -SiO 2 mixture from sodium aluminate, sodium hydroxide sodium silicate and water to provide a molar composition of 15±2Na 2 O 1 al 2 O 3 14±2 siO 2 350±50 h 2 o and mixing vigorously at a temperature of or below 35° C., and (ii) aging the mixture at a temperature of or below about 25° C. for at least 2 hours; and (c) reacting the mixture at a temperature of about 60 to 150° C. for a period of time sufficient to produce a substantially theoretical yield of crystalline zeolite.
Claim 2
Independent Claim
201 words
A method for preparing a crystalline aluminosilicate zeolite which comprises: (a) Preparing an aqueous precursor mixture of silica, alumina and alkali metal hydroxide, the proportions of said silica, alumina and alkali metal hydroxide being those required to produce the desired zeolite; (b) Adding to said precursor mixture from about 0.1 to about 10 percent by weight based on the weight of the theoretical yield of desired zeolite of amorphous aluminosilicate nucleation centers having the molar composition 0.9±0.1 Na 2 O:Al 2 O 3 :2.3-2.7 SiO 2 having an average particle size below 0.1 micron prepared by a process which comprises: (i) preparing an Na 2 O-Al 2 O 3 -SiO 2 mixture from sodium aluminate, sodium hydroxide sodium silicate and water to provide a molar composition of 15±2Na 2 O 1 al 2 O 3 14±2 siO 2 350±50 h 2 o and mixing vigorously at a temperature of or below 35° C., and (ii) aging the mixture at a temperature of or below about 25° C. for at least 2 hours; and (c) reacting the mixture at a temperature of about 60 to 150° C. for a period of time sufficient to produce a substantially theoretical yield of crystalline zeolite.
Claim 3
Dependent Claim
11 words
The method of claim 1 wherein the zeolite is synthetic faujasite.
Claim 4
Dependent Claim
11 words
The method of claim 2 wherein the zeolite is type X.
Claim 5
Dependent Claim
11 words
The method of claim 2 wherein the zeolite is type Y.
Claim 6
Dependent Claim
17 words
The method of claim 2 wherein the reacting period ranges from about 5 minutes to 4 hours.
Claim 7
Dependent Claim
24 words
The method of claim 2 wherein the average particle size of said finely divided nucleation centers ranges from about 0.01 to about 0.1 microns.
Claim 8
Dependent Claim
13 words
The method of claim 2 wherein the alkali metal hydroxide is sodium hydroxide.
Claim 9
Dependent Claim
19 words
The method of claim 2 wherein the silica to alumina ratio of the zeolite is greater than about 4.
Claim 10
Dependent Claim
14 words
The method of claim 6 wherein the silica is derived from soluble sodium silicate.
Claim 11
Dependent Claim
19 words
The method of claim 7 wherein the silica to alumina ratio of the zeolite is greater than about 4.5.
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) | 1982-08-27 | 1983-02-26 | 1983-08-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-08-27 | 1987-02-26 | 1987-08-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-08-27 | 1991-02-26 | 1991-08-28 | $7700.00 | Window Closed / Lapsed |