Organic compounds -- part of the class 532-570 series – Organic compounds – Amino nitrogen containing
Reexamination Certificate
2007-04-24
2007-04-24
Davis, Brian (Department: 1621)
Organic compounds -- part of the class 532-570 series
Organic compounds
Amino nitrogen containing
C564S497000, C558S435000, C540S612000
Reexamination Certificate
active
10939144
ABSTRACT:
The invention relates to the field of separation by distillation of 6-aminocapronitrile (ACN) and hexamethylenediamine (HMD) from a mixture comprising ACN, HMD, tetrahydroazepine (THA), adiponitrile (ADN) and low boilers (LB). Also disclosed is a method for producing a distillate stream comprising HMD; a side draw stream comprising ACN, THA and low levels of dimers of ACN and HMD; and a tails stream comprising ACN, THA and substantially higher levels of dimers of ACN and HMD than found in the side draw stream. The side draw stream is particularly suitable for use in the production of caprolactam since the low levels of dimers of ACN and HMD do not greatly affect the catalyst life in the caprolactam production process. The tails stream can be further distilled to produce a tails distillate stream comprising ACN and THA, which can be recycled back to the first distillation column, further increasing recovery of ACN from the feed stream. Process conditions of the method of the invention disfavor the production of 2-cyanocyclopentylideneimine (CPI).
REFERENCES:
patent: 6139693 (2000-10-01), Bassler et al.
patent: 6248926 (2001-06-01), Ostermaier et al.
Davis Brian
Invista North America S.A R.L.
LandOfFree
Separation of 6-aminocapronitrile and hexamethylenediamine... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Separation of 6-aminocapronitrile and hexamethylenediamine..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Separation of 6-aminocapronitrile and hexamethylenediamine... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3800634