Patent US4235751A successfully refreshed from Google Patents.
US4235751A
Expired / Lapsed
US
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Modified montmorillonite clay catalyst
Assignee: EIDP Inc
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Filing: 1979-04-30
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Granted: 1980-11-25
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Expires: 1999-04-30
Abstract
Abstract A modified montmorillonite clay is prepared by heating it, impregnating it with an organic liquid, acid-activating it with a strong acid, and then washing it with water until it is substantially free of acid anions. The modified clay is useful as a catalyst, particularly for the preparation of tetrahydrofuran/alkylene oxide copolymers.
Inventors
- 👤 Thomas W. Del Pesco
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:54
CPC Classifications
C; C08; C08G; C08G65/00; C08G65/02; C08G65/04; C08G65/06; C08G65/16; C08G65/20; B; B01; B01J; B01J21/00; B01J21/16; C08G65/26; C08G65/2642; C08G65/2645; C08G65/2654; C08G65/2657
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
106 words
A catalyst material prepared by (a) holding a raw granular Wyoming bentonite at a temperature of about 300°-600° C. for about 1-20 hours, in air; (b) impregnating the product of (a) with an organic liquid capable of being intercalated into said product; (c) optionally, removing residual organic liquid from the product of (b); (d) activating the product of (b) or (c) with a strong acid; (e) removing residual acid from the product of (d); (f) washing the product of (e) with water until it is substantially free of acid anions; and then (g) optionally, drying the product of (f) at a temperature below about 150° C.
Claim 2
Dependent Claim
106 words
A catalyst material prepared by (a) holding a raw granular Wyoming bentonite at a temperature of about 300°-600° C. for about 1-20 hours, in air; (b) impregnating the product of (a) with an organic liquid capable of being intercalated into said product; (c) optionally, removing residual organic liquid from the product of (b); (d) activating the product of (b) or (c) with a strong acid; (e) removing residual acid from the product of (d); (f) washing the product of (e) with water until it is substantially free of acid anions; and then (g) optionally, drying the product of (f) at a temperature below about 150° C.
Claim 3
Dependent Claim
17 words
The catalyst material of claim 1 in whose preparation the acid is step (d) is hydrochloric acid.
Claim 4
Dependent Claim
17 words
The catalyst material of claim 1 in whose preparation the organic liquid in step (b) is tetrahydrofuran.
Claim 5
Dependent Claim
95 words
A catalyst material prepared by (a) holding a raw granular Wyoming bentonite at a temperature of about 300°-600° C. for about 1-20 hours, in air; (b) impregnating the product of (a) with tetrahydrofuran; (c) optionally, removing residual tetrahydrofuran from the product of (b); (d) activating the product of (b) or (c) with hydrochloric acid; (e) removing residual acid from the product of (d); (f) washing the product of (e) with water until it is substantially free of chloride ions; and then (g) optionally, drying the product of (f) at a temperature below about 150° C.
Claim 6
Dependent Claim
95 words
A catalyst material prepared by (a) holding a raw granular Wyoming bentonite at a temperature of about 300°-600° C. for about 1-20 hours, in air; (b) impregnating the product of (a) with tetrahydrofuran; (c) optionally, removing residual tetrahydrofuran from the product of (b); (d) activating the product of (b) or (c) with hydrochloric acid; (e) removing residual acid from the product of (d); (f) washing the product of (e) with water until it is substantially free of chloride ions; and then (g) optionally, drying the product of (f) at a temperature below about 150° C.
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) | 1983-11-25 | 1984-05-26 | 1984-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-11-25 | 1988-05-26 | 1988-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-11-25 | 1992-05-26 | 1992-11-25 | $7700.00 | Window Closed / Lapsed |