US4381255A
Expired / Lapsed
US
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Binderless zeolite extrudates and method of producing
Assignee: WR Grace and Co Conn
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Filing: 1981-01-14
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Granted: 1983-04-26
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Expires: 2001-01-14
Abstract
Abstract Binderless zeolite sieve extrudates are made by extruding a mixture containing about 40-60% zeolites with the remainder being a metakaolin clay that has mixed with it about 90-120% of the stoichiometric amount of sodium hydroxide to convert the clay to a zeolite. After extrusion the particles are allowed to dry age during which time most of the clay is converted to the zeolite. A further heat treatment in a dilute caustic aqueous solution insures complete crystallization with subsequent washing and calcination to produce an adsorbent product.
Inventors
- 👤 Richard J. Nozemack
- 👤 Chang W. Chi
- 👤 John J. Schwonke
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 01:57
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/20; C01B33/26; C01B33/28; C01B33/2807; C01B33/2815; C01B33/283
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
160 words
Process of producing binderless zeolite sieve extrudates containing at least Type A Zeolite from clay and a synthetic zeolite, said extrudates having a higher adsorption capacity, a faster adsorption rate, improved selectivity, and improved attrition resistance, said process comprising (a) forming an extrudable mixture of (i) a synthetic zeolite, (ii) metakaolin clay, (iii) sodium hydroxide solution said clay comprising about 40-60% by weight of the total weight of the clay and the zeolite on a dry basis and the amount of sodium hydroxide being in the range of about 90-120% of the stoichiometric amount to convert the clay to a zeolite; (b) extruding the mixture of step (a) to form extrudates; (c) aging the extrudates; (d) treating the extrudates with a dilute solution of sodium hydroxide at an elevated temperature to complete the crystallization of the aged extrudates; (e) washing the extrudates; and (f) recovering the washed extrudates and dry calcining them whereby they can be used as selected adsorbents.
Claim 2
Dependent Claim
160 words
Process of producing binderless zeolite sieve extrudates containing at least Type A Zeolite from clay and a synthetic zeolite, said extrudates having a higher adsorption capacity, a faster adsorption rate, improved selectivity, and improved attrition resistance, said process comprising (a) forming an extrudable mixture of (i) a synthetic zeolite, (ii) metakaolin clay, (iii) sodium hydroxide solution said clay comprising about 40-60% by weight of the total weight of the clay and the zeolite on a dry basis and the amount of sodium hydroxide being in the range of about 90-120% of the stoichiometric amount to convert the clay to a zeolite; (b) extruding the mixture of step (a) to form extrudates; (c) aging the extrudates; (d) treating the extrudates with a dilute solution of sodium hydroxide at an elevated temperature to complete the crystallization of the aged extrudates; (e) washing the extrudates; and (f) recovering the washed extrudates and dry calcining them whereby they can be used as selected adsorbents.
Claim 3
Dependent Claim
17 words
The process of claim 1, where the sodium hydroxide solution in step (a) is a chilled solution.
Claim 4
Dependent Claim
20 words
The process of claim 1, wherein the amount of sodium hydroxide in step (a) is 110% of the stoichiometric amount.
Claim 5
Dependent Claim
24 words
The process of claim 1, wherein the amount of clay comprises about 50% by weight of the total weight of the clay and zeolite.
Claim 6
Dependent Claim
29 words
The process of claim 1, wherein the extrudates in step (c) are aged under dry, ambient conditions to permit them to withstand the elevated temperature treatment in step (d).
Claim 7
Dependent Claim
30 words
The process of claim 1, wherein the crystallized extrudates from step (d) are treated with a calcium ion exchange to convert the nominal 4A zeolites present to nominal 5A zeolites.
Claim 8
Dependent Claim
17 words
The process of claim 1, wherein the dilute solution in step (d) contains about 3% sodium hydroxide.
Claim 9
Dependent Claim
12 words
The binderless zeolite sieve extrudate made by the process of claim 1.
Claim 10
Dependent Claim
12 words
The binderless zeolite sieve extrudate made by the process of claim 6.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-04-25 | 1986-10-25 | 1987-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-25 | 1990-10-25 | 1991-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-25 | 1994-10-25 | 1995-04-26 | $7700.00 | Window Closed / Lapsed |