Patent USRE28629E successfully refreshed from Google Patents.
USRE28629E
Expired / Lapsed
US
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Ion exchange of crystalline zeolites
Assignee: —
•
Filing: 1970-09-10
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Granted: 1975-11-25
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Expires: 1990-09-10
Abstract
Abstract Method of cation exchanging zeolites comprising a conventional ion exchange step, whereby the more easily exchangeable cations are ion exchanged, followed by a calcination step at 400* to 1500* F., whereby the difficult to exchange cations are redistributed, the redistributed cations are then ion exchanged by an additional conventional ion exchange step. One or more calcinations and additional ion exchange steps may be used. This method is particularly applicable to the ion exchange removal of sodium ions from crystalline zeolites.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:54
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/02; B01J20/10; B01J20/16; B01J20/18; B01J20/186; B01J29/00; B01J29/04; B01J29/06; B01J29/08; B01J29/082; B01J29/084; B01J2229/00; B01J2229/30; B01J2229/40
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
93 words
A PROCESS OF CATION EXCHANING CRYSTALLINE ZEOLITE ALUMINOSILICATES, INCLUDING EXCHANGING LOCKED-IN CATIONS COMPRISING: (A) EXCHANGING THE ZEOLITE WITH A SOLUTION OF A SALT OF AT LEAST ONE DESIRED METAL CATION TO AN ORIGINAL CATION CONTENT OF LESS THAN 3-4% BY WEIGHT, (B) WASHING TO REMOVE EXCESS SALTS, (C) DRYING AND HEATING THE EXCHANGED ZEOLITE AT A TEMPERATURE OF 400* TO 1500* F TO REDISTRIBUTE THE LOCKED-IN CATIONS FOR EACH EXCHANGE, (D) COOLING THE CALCINED ZEOLITE AND REDUCING THE ORIGINAL CATION CONTENT BY A SECOND ION EXCHANGE (E) WASHING, DRYING AND RECOVERING THE PRODUCT.
Claim 2
Dependent Claim
93 words
A PROCESS OF CATION EXCHANING CRYSTALLINE ZEOLITE ALUMINOSILICATES, INCLUDING EXCHANGING LOCKED-IN CATIONS COMPRISING: (A) EXCHANGING THE ZEOLITE WITH A SOLUTION OF A SALT OF AT LEAST ONE DESIRED METAL CATION TO AN ORIGINAL CATION CONTENT OF LESS THAN 3-4% BY WEIGHT, (B) WASHING TO REMOVE EXCESS SALTS, (C) DRYING AND HEATING THE EXCHANGED ZEOLITE AT A TEMPERATURE OF 400* TO 1500* F TO REDISTRIBUTE THE LOCKED-IN CATIONS FOR EACH EXCHANGE, (D) COOLING THE CALCINED ZEOLITE AND REDUCING THE ORIGINAL CATION CONTENT BY A SECOND ION EXCHANGE (E) WASHING, DRYING AND RECOVERING THE PRODUCT.
Claim 3
Dependent Claim
14 words
The process of claim 1 wherein the original cation is an alkali metal cation.
Claim 4
Dependent Claim
26 words
The process of claim 1 wherein the redistribution heating step and cation exchange step is effected as a series of alternating calcination and cation exchange steps.
Claim 5
Dependent Claim
13 words
The process of claim 1 wherein the desired cation is a polyvalent cation.
Claim 6
Dependent Claim
11 words
The process of claim 1 wherein the desired cation is bivalent.
Claim 7
Dependent Claim
23 words
The process of claim 1 wherein the zeolite is a zeolite from the group consisting of type Y, type X and type A.
Claim 8
Dependent Claim
19 words
The process of claim 1 wherein the temperature of the ion exchange solutions is from 50* to 90* C.
Claim 9
Dependent Claim
15 words
The process of claim 1 wherein the drying and heating temperature is between 800*-1200* F.
Claim 10
Dependent Claim
16 words
The process of claim 2 wherein the desired metal cation is a rare earth metal cation.
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) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |