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:
Aug. 04, 1981
Filed:
Nov. 14, 1977
Applicant:
Inventors:
Frederick C Franklin, Pinole, CA (US);
Stephen G Paradis, Fairfax, CA (US);
Assignee:
Chevron Research Company, San Francisco, CA (US);
Primary Examiner:
Int. Cl.
CPC ...
B01D / ;
U.S. Cl.
CPC ...
55 48 ; 55 51 ; 55 55 ; 26034676 ;
Abstract
In a reduced-pressure process for distilling crude maleic anhydride recovered by separation from an organic absorbent wherein reduced pressure is obtained using a liquid ring-seal vacuum pump, the improvement which comprises sealing the liquid ring-seal vacuum pump by circulating a maleic anhydride absorbent from a regenerating zone through the vacuum pump chamber.