Process for the synthesis of epsilon-caprolactam
US4789741A · kind A · utility
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1References
6Claims
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Assignee
Inventors
Key dates
| Filing date | Mar 7, 1988 |
| Grant date | Dec 6, 1988 |
| Priority date | — |
| Expiry date | Mar 7, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J2219/00119
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
The invention concerns a two-step process for the synthesis of caprolactam by reaction of cylcohexanone-oxime with an excess of oleum, carried out in a first step with only a portion of the oxime and in the presence of liquid SO.sub.2, according to usual "cold" techniques, the amount of free SO.sub.3 in the oleum being equal to or greater than 50% by weight, wherein said "cold" step is completed by a second "hot" step, by adding a second portion of oxime, the ratio between said second portion and said first portion ranging from 0.5 to 1.2.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.