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US4142871A
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Preparation of abrasive material from spent catalysts
Assignee: Treibacher Chemische Werke AG
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Filing: 1977-10-25
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Granted: 1979-03-06
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Expires: 1997-10-25
Abstract
Abstract An abrasive material is prepared from a starting material comprised of a spent metallic catalyst on an alumina carrier by melting the starting material with a reducing agent to obtain a melt consisting of a melt component including the alumina on an alloy residue, cooling the melt at a speed correlated with a desired crystallite size of the abrasive material to be obtained, and mechanically separating the melt component from the alloy residue before or after solidification, the melt component constituting the abrasive material.
Inventors
- 👤 Hans Zeiringer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 11:13
CPC Classifications
C; C09; C09K; C09K3/00; C09K3/14; C09K3/1409; C09K3/1427; C04; C04B; C04B35/00; C04B35/622; C04B35/653; C09K3/1418
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
93 words
A process for preparing an alumina abrasive material from a starting material comprised of a spent heavy metal alloy catalyst on an alumina carrier, comprising the steps of melting the starting material with at least one reducing agent to obtain a melt consisting of a melt component including the alumina on a residue of the alloy, cooling the melt at a speed correlated with a desired crystallite size of the abrasive material to be obtained, and mechanically separating the alumina-containing melt component from the alloy residue, the melt component constituting the abrasive material.
Claim 2
Dependent Claim
93 words
A process for preparing an alumina abrasive material from a starting material comprised of a spent heavy metal alloy catalyst on an alumina carrier, comprising the steps of melting the starting material with at least one reducing agent to obtain a melt consisting of a melt component including the alumina on a residue of the alloy, cooling the melt at a speed correlated with a desired crystallite size of the abrasive material to be obtained, and mechanically separating the alumina-containing melt component from the alloy residue, the melt component constituting the abrasive material.
Claim 3
Dependent Claim
20 words
The process of claim 1, wherein the starting material is melted with at least one reducing agent consisting of carbon.
Claim 4
Dependent Claim
12 words
The process of claim 1, wherein the carbon reducing agent is coke.
Claim 5
Dependent Claim
18 words
The process of claim 1, wherein the melt component comprises at least a portion of the reducing agent.
Claim 6
Dependent Claim
36 words
The process of claim 1, wherein at least one additive selected from the group consisting of zirconia, titania, chromic oxide, lime, magnesia, silica, zinc oxide and a rare earth oxide is added to the melt component.
Claim 7
Dependent Claim
20 words
The process of claim 5, wherein about 5% to 60%, by weight, or zirconia is added to the melt component.
Claim 8
Dependent Claim
19 words
The process of claim 5, wherein up to 10%, by weight, of titania is added to the melt component.
Claim 9
Dependent Claim
17 words
The process of claim 1, wherein the melt component is separated from the alloy residue before solidification.
Claim 10
Dependent Claim
17 words
The process of claim 1, wherein the melt component is separated from the alloy residue after solification.
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) | 1982-03-05 | 1982-09-04 | 1983-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-05 | 1986-09-04 | 1987-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-05 | 1990-09-04 | 1991-03-06 | $7700.00 | Window Closed / Lapsed |