Method for purifying N-(2-hydroxyethyl)-2-pyrrolidone

Details Method for purifying N-(2-hydroxyethyl)-2-pyrrolidone Method for purifying N-(2-hydroxyethyl)-2-pyrrolidone

2006-05-16

2006-05-16

McKane, Joseph K. (Department: 1626)

Organic compounds -- part of the class 532-570 series

Organic compounds

Heterocyclic carbon compounds containing a hetero ring...

Reexamination Certificate

active

07045639

ABSTRACT:
A method for purifying N-(2-hydroxyethyl)-2-pyrrolidone (HEP) is disclosed. The method comprises crystallizing crude HEP to produce HEP crystals and a mother liquor, and separating the HEP crystals from the mother liquor. In one method of the invention, crystallization is induced by adding an HEP seed crystal to the crude HEP. In a preferred method, the crystallization is performed in the presence of 1–4 wt. % of added water. HEP can be successfully crystallized to a purity greater than 99.9%.

REFERENCES:
patent: 2669570 (1954-02-01), Schnizer
patent: 3875184 (1975-04-01), Hort
patent: 5801252 (1998-09-01), Yano et al.
patent: 2002/0139657 (2002-10-01), Ugamura et al.
patent: 1072429 (1967-06-01), None
patent: 1072429 (1967-06-01), None

Affiliated with

Also associated with

Rating

Method for purifying N-(2-hydroxyethyl)-2-pyrrolidone does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for purifying N-(2-hydroxyethyl)-2-pyrrolidone, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for purifying N-(2-hydroxyethyl)-2-pyrrolidone will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3532175