EP0021675A2
Expired / Lapsed
EP
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Continuous-stream method of preparing crystalline zeolites
Assignee: Mobil Oil AS
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Filing: 1980-06-06
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Granted: —
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Expires: 2000-06-06
Abstract
Abstract A method for preparing a crystalline zeolite, with a constraint index of between 1 and 12 and a SiO 2 /Al 2 O 3 ratio grea- - ter than 12 on a continuous-stream basis. An aqueous reaction mixture composition having an OH / SiO 2 mole ratio less than 1 is passed in a continuous stream through a heated reactor zone to produce a slurry of zeolite.
Inventors
- 👤 Louis Deane Rollmann
- 👤 Ernest William Valyocsik
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-02 16:23
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/20; C01B33/26; C01B33/28; C01B33/2807; C01B33/2876
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
1 words
.
Claim 2
Independent Claim
143 words
A method for preparing a crystalline zeolite having a constraint index between 1 and 12 and a Si0 2 /A1 2 0 3 ratio greater than 12 on a continuous stream basis which comprises preparing a mixture containing sources of an alkali metal oxide, R 2 0, an oxide of aluminum, an oxide of silicon and water under controlled amounts of the resultant hydroxyl, silica and alumina components and having a composition, in terms of mole ratios of oxides, falling within the following ranges: wherein R is a tetrapropylammonium cation or an amine having a pK a greater than about 7, said mixture being introduced in a continuous stream, and maintaining the mixture at a temperature between about 50 and 250°C, at LHSV between 0.01 and 10 at a pressure between about 1 and 60 atmospheres until crystals of said zeolite are formed.
Claim 3
Dependent Claim
23 words
The method of Claim 1 wherein the mixture has a composition, in terms of mole ratios of oxides, falling within the following ranges:
Claim 4
Independent Claim
20 words
The method according to Claims 1 and 2 wherein the temperature is maintained between from about 160°C to about 210°C.
Claim 5
Independent Claim
31 words
The method of Claims 1, 2 and 3 wherein said sources of an alkali metal oxide, R 2 0, an oxide of aluminum, and an oxide of silicon are introduced step-wise.
Claim 6
Dependent Claim
24 words
The method according to Claim 4 wherein modifiers including acids and bases are introduced step-wise into the- reaction mixture for pH control during crystallization.
Claim 7
Independent Claim
21 words
The method according to Claims 1 and 2 wherein seed crystals of the product zeolite are introduced into the reaction mixture.
Claim 8
Dependent Claim
96 words
In a method for preparing a crystalline zeolite having a constraint index between about 1 and 12 and a silica/alumina ratio greater than 12 from a reaction mixture containing sources of an alkali metal oxide, R 2 0, an oxide of aluminum, an oxide of silicon and water, wherein R is a tetrapropylammonium cation or an amine having a pK a greater than about 7, and maintaining said mixture under crystallization conditions, the improvement which comprises conducting said crystallization at a resultant OH /Si0 2 ratio of less than 1 and on a continuous stream basis.
Claim 9
Dependent Claim
31 words
The method according to Claim 7 wherein a further improvement comprises introducing said sources of an alkali metal oxide, R 2 0,-an oxide of aluminum, and an oxide of silicon step-wise.
Claim 10
Dependent Claim
10 words
The method of Claim 1 wherein said zeolite is ZSM-5.
Claim 11
Dependent Claim
19 words
The crystalline zeolites produced by the method of Claims 1, 2, 3, 4, 5, 6, 7, 8, and 9.
References Cited (Backward Citations)
No citation records indexed.
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