The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 27, 1977
Filed:
Nov. 26, 1976
Applicant:
Inventor:
Byron E Anshus, Orinda, CA (US);
Assignee:
Chevron Research Company, San Francisco, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
B01D / ; C07D / ;
U.S. Cl.
CPC ...
203 35 ; 203 14 ; 203 47 ; 203 73 ; 260 / ; 2603 / ;
Abstract
A two-stage evaporative method for recovering polymerizable 2-pyrrolidone from alkaline aqueous solutions such as those obtained by washing the catalyst from an incompletely reacted polypyrrolidone polymerizate, includes the steps of neutralizing the base with mineral acid, removing most of the water in an initial reduced pressure evaporation and recovering the pyrrolidone from a salt/pyrrolidone slurry by vaporization under reduced pressure.