US5026531A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Silicate treatment of molecular sieve agglomerates
Assignee: Honeywell UOP LLC
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Filing: 1989-02-10
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Granted: 1991-06-25
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Expires: 2009-02-10
Abstract
Abstract Molecular sieve agglomerates that can have improved physical and chemical properties are prepared by methods which comprise contacting the agglomerates with an alkali metal silicate solution. Molecular sieve agglomerates which comprise binders such as kaolin can additionally be contacted with an alkali hydroxide solution to convert the kaolin to Zeolite A prior to contacting the agglomerates with the alkali metal silicate solution to further improve properties. The molecular sieve agglomerates prepared according to the present invention are suitable for use as refrigerant desiccants.
Inventors
- 👤 Medhat K. Tannous
- 👤 John D. Sherman
- 👤 Alan P. Cohen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 18:43
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/16; B01J20/18; B01J20/186; Y; Y10; Y10S; Y10S423/00; Y10S423/24
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
128 words
Method for preparing attrition resistant molecular sieve agglomerates, comprising: (a) forming an initial agglomerate comprising zeolite and binder selected from the group consisting of metal oxides, clays, silicas, aluminas, silica-aluminas, silica-zierconias, silica-thorisas, silica-berylias, silica-titanias, silica-alumina-thorias, silica-alumina-zirconias and mixtures thereof. (b) heating the initial agglomerate at a temperature within the range of from about 200-700° C. and sufficient to set the binder and form a calcined agglomerate; (c) contacting the calcined agglomerate with an aqueous alkali metal silicate solution containing from about 1 to 10 wt. % alkali metal oxide and from about 2 to 20 wt. % silicon dioxide to form a treated agglomerate; and (d) drying the treated agglomerate at a temperature of from about ambient temperature to about 650° C. and sufficient to remove water therefrom.
Claim 2
Dependent Claim
128 words
Method for preparing attrition resistant molecular sieve agglomerates, comprising: (a) forming an initial agglomerate comprising zeolite and binder selected from the group consisting of metal oxides, clays, silicas, aluminas, silica-aluminas, silica-zierconias, silica-thorisas, silica-berylias, silica-titanias, silica-alumina-thorias, silica-alumina-zirconias and mixtures thereof. (b) heating the initial agglomerate at a temperature within the range of from about 200-700° C. and sufficient to set the binder and form a calcined agglomerate; (c) contacting the calcined agglomerate with an aqueous alkali metal silicate solution containing from about 1 to 10 wt. % alkali metal oxide and from about 2 to 20 wt. % silicon dioxide to form a treated agglomerate; and (d) drying the treated agglomerate at a temperature of from about ambient temperature to about 650° C. and sufficient to remove water therefrom.
Claim 3
Dependent Claim
22 words
Method of claim 1 wherein said zeolite is the potassium-exchanged form of Zeolite A having uniform pore diameters of about 3 Angstroms.
Claim 4
Dependent Claim
22 words
Method of claim 1 wherein said zeolite is the sodium-exchanged from of Zeolite A having uniform pore diameters of about 4 Anstroms.
Claim 5
Dependent Claim
22 words
Method of claim 1 wherein the binder comprises from about 5 percent to about 40 percent by weight of said initial agglomerate.
Claim 6
Dependent Claim
22 words
Method of claim 1 wherein the binder is a clay binder selected from the group consisting of kaolin, attapulgite and mixtures thereof.
Claim 7
Dependent Claim
12 words
Method of claim 1 wherein the alkali metal oxide is potassium oxide.
Claim 8
Dependent Claim
24 words
Method of claim 1 wherein said drying is conducted by heating in air to a temperature of from about 200° C. to 650° C.
Claim 9
Dependent Claim
10 words
Method of claim 1 wherein the binder is kaolin clay.
Claim 10
Dependent Claim
25 words
Method of claim 8 wherein the temperature sufficient to set the binder in said initial agglomerate is from about 550° C. to about 650° C.
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