http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-669903-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_f7626330f09df8cac7928e91ef5133e6 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D223-10 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D201-00 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D201-04 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D201-16 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07D201-08 |
| filingDate | 1949-03-01-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1952-04-09-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-669903-A |
| titleOfInvention | A method of isolating lactams |
| abstract | Lactams made by the Beckmann re-arrangement of cyclic ketoximes in hot sulphuric acid or oleum are isolated by treating the raw lactam with superheated steam and are subsequently separated by known methods, e.g. by crystallization or vacuum distillation. Steam treatment is preferably effected at reduced pressure which is not low enough to produce boiling of the lactam. The treatment removes impurities which cause turbidity in aqueous solutions of lactams and to prevent turbidity it is also necessary to neutralize the acid lactam solutions with an alkali other than ammonia. The raw lactam may contain water. In an example raw 6-caprolactam is treated with superheated steam at 120 DEG C. and 200 m.ms. Hg. until dry when the vacuum is increased to 8-10 m.ms. Hg. and the lactam distilled at 140 DEG C. Specification 666,717 is referred to.ALSO:Lastams made by the Beckmann rearrangement of cyclic ketoximes in hot sulphuric acid or oleum are isolated by treating the raw lactam with superheated steam and are subsequently separated by known methods, e.g. by crystallization or vacuum distillation. Steam treatment is preferably effected at reduced pressure which is not low enough to make the lactam boil. The treatment removes impurities which cause turbidity in aqueous solutions of lactams. The raw lactam may contain water. In an example raw 6-capiolactam is treated with superheated steam at 120 DEG C. and 200 m.ms. Hg. until dry when the vacuum is increased to 8-10 m.ms. Hg. and the lactam distilled at 140 DEG C. |
| isCitedBy | http://rdf.ncbi.nlm.nih.gov/pubchem/patent/US-2866785-A http://rdf.ncbi.nlm.nih.gov/pubchem/patent/DE-1022591-B |
| priorityDate | 1948-03-02-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 23.