US4073867A
Expired / Lapsed
US
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Process for the production of crystalline zeolitic molecular sieves of type A
Assignee: Evonik Operations GmbH
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Filing: 1976-03-30
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Granted: 1978-02-14
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Expires: 1996-03-30
Abstract
Abstract A crystalline zeolitic molecular sieve of Type A with the composition 1.0 ± 0.2 M 2/n O : Al 2 O 3 : 1.85 ± 0.5 SiO 2 . y H 2 O where M is a metal cation, n its valence and y has a value up to 6 is prepared having particles with at least 99.5 weight % below 30μ diameter, as well as at least 90 weight % under 10μ and with 50 weight % below 6.5μ by hydrothermal crystallization of an alkali-aluminate silicate by pouring together an aqueous alkali silicate solution and a slightly concentrated aqueous alkali aluminate liquor, in a given case with simultaneous stirring in a receiver, allowing the synthesis premixture to solidify to a gel, adding to this gel a more highly concentrated aqueous alkali aluminate liquor at a temperature between 10° and 100° C. while stirring, allowing the thus obtained synthesis mixture to crystallize at a temperature between 20° and 175° C., preferably 100° C., within 15 minutes and in a given case including a tempering step.
Inventors
- 👤 Wolfgang Roebke
- 👤 Dieter Kneitel
- 👤 Erfried Parr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 05:14
CPC Classifications
C; C11; C11D; C11D3/00; C11D3/02; C11D3/12; C11D3/124; C11D3/1246; C11D3/128; 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: 11
Claim 1
Independent Claim
225 words
A process for producing a crystalline zeolitic molecular sieve of Type A with the composition 1.0 ± 0.2 Na.sub.2/n O : Al.sub.2 O.sub.3 : 1.85 ± 0.5 SiO.sub.2. y H.sub.2 O where y has a value up to 6 having particles with at least 99.5 weight % below 30μ diameter, as well as at least 90 weight % under 10μ and with 50 weight % below 6.5μ and having the particle spectrum ______________________________________
Fraction (μ) Portion (weight %)
______________________________________
<5 25-35
<10 90-93
<15 91-97
<20 93-98
______________________________________ comprising hydrothermally crystallizing a sodium aluminate silicate by pouring together while stirring an aqueous sodium silicate solution and a first aqueous sodium aluminate liquor containing 1 to 100 g Al 1 O 3 /l and 10 to 200 g Na 2 O/l, allowing the synthesis premixture formed having the molar ratios ______________________________________
SiO.sub.2 /Al.sub.2 O.sub.3
3.4 to 50:1
Na.sub.2 O/SiO.sub.2
0.2 to 20:1
H.sub.2 O /Na.sub.2 O
4 to 300:1
______________________________________ to solidify to a gel, adding to this gel a second and more highly concentrated aqueous sodium aluminate liquor containing up to 200 g Al 2 O 3 /l and up to 250 g Na 2 O/l at a temperature between 10° and 100° C while stirring, allowing the thus obtained synthesis mixture to crystallize at a temperature between 20° and 175° C within 15 minutes.
Claim 2
Dependent Claim
225 words
A process for producing a crystalline zeolitic molecular sieve of Type A with the composition 1.0 ± 0.2 Na.sub.2/n O : Al.sub.2 O.sub.3 : 1.85 ± 0.5 SiO.sub.2. y H.sub.2 O where y has a value up to 6 having particles with at least 99.5 weight % below 30μ diameter, as well as at least 90 weight % under 10μ and with 50 weight % below 6.5μ and having the particle spectrum ______________________________________
Fraction (μ) Portion (weight %)
______________________________________
<5 25-35
<10 90-93
<15 91-97
<20 93-98
______________________________________ comprising hydrothermally crystallizing a sodium aluminate silicate by pouring together while stirring an aqueous sodium silicate solution and a first aqueous sodium aluminate liquor containing 1 to 100 g Al 1 O 3 /l and 10 to 200 g Na 2 O/l, allowing the synthesis premixture formed having the molar ratios ______________________________________
SiO.sub.2 /Al.sub.2 O.sub.3
3.4 to 50:1
Na.sub.2 O/SiO.sub.2
0.2 to 20:1
H.sub.2 O /Na.sub.2 O
4 to 300:1
______________________________________ to solidify to a gel, adding to this gel a second and more highly concentrated aqueous sodium aluminate liquor containing up to 200 g Al 2 O 3 /l and up to 250 g Na 2 O/l at a temperature between 10° and 100° C while stirring, allowing the thus obtained synthesis mixture to crystallize at a temperature between 20° and 175° C within 15 minutes.
Claim 3
Dependent Claim
15 words
The process of claim 1 wherein the crystallization is carried out at about 100° C.
Claim 4
Dependent Claim
25 words
The process of claim 1 wherein the crystallization is followed a tempering in the crystallization mother liquor for a time of 0.2 to 6 hours.
Claim 5
Dependent Claim
16 words
The process of claim 3 wherein the tempering is carried out at 85° to 105° C.
Claim 6
Dependent Claim
30 words
The process of claim 1 wherein the sodium silicate and the first sodium aluminate are reacted in the presence of aqueous sodium hydroxide containing 0.1 to 500 grams of NaOH/l.
Claim 7
Dependent Claim
39 words
The process of claim 1 wherein the synthesis premixture molar ratios are SiO 2 /Al 2 O 3 : 3.4 to 40:1 Na 2 O/SiO 2 : 0.2 to 0.5:1 H 2 o/na 2 O : 4 to 200:1
Claim 8
Dependent Claim
40 words
The process of claim 1 wherein the more highly concentrated alkali aluminate liquor is a sodium aluminate liquor having from above 100 to 200 grams Al 2 O 3 /l and from above 100 to 250 grams Na 2 O/l.
Claim 9
Dependent Claim
22 words
The process of claim 7 wherein the more highly concentrated sodium aluminate has 100 to 150 grams Al 2 O 3 /l.
Claim 10
Dependent Claim
32 words
The process of claim 7 wherein the more highly concentrated sodium aluminate liquor has 111 to 200 grams Al 2 O 3 /l and from 170 to 250 grams Na 2 O/l.
Claim 11
Dependent Claim
20 words
The process of claim 1 comprising employing shearing forces in at least one of the steps of crystallization and tempering.
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) | 1981-02-13 | 1981-08-15 | 1982-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-13 | 1985-08-15 | 1986-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-13 | 1989-08-15 | 1990-02-14 | $7700.00 | Window Closed / Lapsed |