US4360461A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for obtaining caprolactam by cleaving caprolactam oligomers
Assignee: BASF SE
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Filing: 1981-07-28
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Granted: 1982-11-23
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Expires: 2001-07-28
Abstract
Abstract In a process for obtaining caprolactam by cleaving caprolactam oligomers by passing them through an alumina catalyst bed at an elevated temperature, the improvement that the oligomers are introduced, as liquid or solid, into a fluidized bed of alumina and are cleaved at from 290° to 400° C. in the presence of steam.
Inventors
- 👤 Hugo Fuchs
- 👤 Elmar Frommer
- 👤 Otto-Alfred Grosskinsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:27
CPC Classifications
C; C08; C08J; C08J11/00; C08J11/02; C07; C07D; C07D201/00; C07D201/02; C07D201/12; C08J2377/00; C08J2377/02
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
53 words
An improved process for obtaining caprolactam by cleaving caprolactam oligomers by passing them through an alumina catalyst bed at an elevated temperature, wherein the improvement comprises introducing the oligomers, as liquid or solid, into a fluidized bed of alumina and cleaving them at from 290° to 400° C. in the presence of steam.
Claim 2
Dependent Claim
53 words
An improved process for obtaining caprolactam by cleaving caprolactam oligomers by passing them through an alumina catalyst bed at an elevated temperature, wherein the improvement comprises introducing the oligomers, as liquid or solid, into a fluidized bed of alumina and cleaving them at from 290° to 400° C. in the presence of steam.
Claim 3
Dependent Claim
30 words
A process as claimed in claim 1, wherein from 0.005 to 10 parts by weight of water, in the form of steam, are used per part by weight of oligomer.
Claim 4
Dependent Claim
19 words
A process as claimed in claim 1, wherein the cleavage is carried out at from 300° to 360° C.
Claim 5
Dependent Claim
21 words
A process as claimed in claim 1, wherein the oligomers are introduced conjointly with caprolactam into a fluidized bed of alumina.
Claim 6
Dependent Claim
13 words
A process as claimed in claim 1, wherein the catalyst used is γ-alumina.
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) | 1985-11-22 | 1986-05-24 | 1986-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-11-22 | 1990-05-24 | 1990-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-11-22 | 1994-05-24 | 1994-11-23 | $7700.00 | Window Closed / Lapsed |