Patent US4652544A successfully refreshed from Google Patents.
US4652544A
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Solid acid catalyst of acid-treated hydrated niobium oxide and method for its preparation
Assignee: CBMM INTERNATIONAL LTDA RUA JOA MANOEL N 923 SAO BAULO BRAZIL
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Filing: 1985-08-21
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Granted: 1987-03-24
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Expires: 2005-08-21
Abstract
Abstract A solid state catalyst consists essentially of hydrated niobium oxide containing a phosphoric acid on its surface in an amount sufficient to increase surface acidity, to inhibit crystallization of the niobium oxide and to retard loss in catalytic activity following exposure to high temperature. The catalyst can be prepared by treating hydrated niobium oxide (Nb 2 O 5 .xH 2 O) or an anhydride thereof with a phosphoric acid. The catalyst is useful in the hydration of ethylene to form ethanol.
Inventors
- 👤 Susumu Okazaki
- 👤 Tokio Iizuka
- 👤 Satoshi Kado
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 18:01
CPC Classifications
C; C07; C07C; C07C29/00; C07C29/03; C07C29/04; B; B01; B01J; B01J27/00; B01J27/14; B01J27/186; B01J27/195
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
53 words
A solid acid catalyst consisting essentially of hydrated niobium oxide containing a phosphoric acid on its surface in an amount sufficient to increase surface acidity of said niobium oxide, to inhibit crystallization of said niobium oxide following exposure to high temperature and to retard loss in catalytic activity following exposure to high temperature.
Claim 2
Dependent Claim
53 words
A solid acid catalyst consisting essentially of hydrated niobium oxide containing a phosphoric acid on its surface in an amount sufficient to increase surface acidity of said niobium oxide, to inhibit crystallization of said niobium oxide following exposure to high temperature and to retard loss in catalytic activity following exposure to high temperature.
Claim 3
Dependent Claim
17 words
Solid acid catalyst according to claim 1 wherein the catalyst has a surface acidity H o ≦-5.6.
Claim 4
Dependent Claim
17 words
Solid acid catalyst according to claim 1 wherein said catalyst contains condensed phosphoric acid on its surface.
Claim 5
Dependent Claim
16 words
Solid acid catalyst according to claim 3 wherein said condensed phosphoric acid is non-volatile polyphosphoric acid.
Claim 6
Dependent Claim
16 words
Solid acid catalyst according to claim 1 which is in the form of finely divided grains.
Claim 7
Dependent Claim
18 words
Solid acid catalyst according to claim 3 wherein said phosphoric acid is widely distributed on the catalyst surface.
Claim 8
Dependent Claim
18 words
Solid acid catalyst according to claim 3 wherein said phosphoric acid is evenly distributed on the catalyst surface.
Claim 9
Dependent Claim
16 words
Solid acid catalyst according to claim 2 wherein said catalyst is resistant to poisoning by water.
Claim 10
Dependent Claim
65 words
A method for preparing a solid acid catalyst as claimed in claim 1 comprising treating hydrated niobium oxide or an anhydride thereof with a phosphoric acid in an amount and under conditions sufficient to increase surface acidity of said niobium oxide, to inhibit crystallization of said niobium oxide following exposure to high temperature and to retard loss in catalytic activity following exposure to high temperature.
Claim 11
Dependent Claim
21 words
Method according to claim 9 wherein said niobium oxide is treated with a 0.5 to 2.0 mol/liter solution of phosphoric acid.
Claim 12
Dependent Claim
22 words
Method according to claim 10 comprising treating said niobium oxide by immersion in orthophosphoric acid and aging the resulting mixture without agitation.
Claim 13
Dependent Claim
31 words
Method according to claim 11 comprising removing treated niobium oxide from said mixture and heating the treated niobium oxide in air at an elevated temperature to dry the treated niobium oxide.
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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) | 1990-03-23 | 1990-09-22 | 1991-03-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-03-23 | 1994-09-22 | 1995-03-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-03-23 | 1998-09-22 | 1999-03-24 | $7700.00 | Window Closed / Lapsed |