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:
Oct. 23, 2007
Filed:
Feb. 07, 2003
Applicants:
Noriaki Oku, Ichihara, JP;
Toshio Nakayama, Sodegaura, JP;
Koji Shinohara, Ichihara, JP;
Inventors:
Assignee:
Sumitomo Chemical Company, Limited, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D 3/40 (2006.01); B01D 3/42 (2006.01); C07D 301/32 (2006.01); C07D 303/04 (2006.01);
U.S. Cl.
CPC ...
Abstract
A process for purifying propylene oxide characterized by subjecting a liquid reaction mixture containing propylene oxide, and water, hydrocarbons and oxygen-containing organic compounds as impurities obtained by reacting cumene hydroperoxide with propylene to extractive distillation using an extractant of a hydrocarbon having 7 to 20 carbon atoms with an extractive distillation column, and controlling a concentration of propylene glycol in the extractant supplied to the extractive distillation column to 20% by weight or less.