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:
Nov. 16, 1993
Filed:
Apr. 19, 1993
Robert A Meyer, St. Louis, MO (US);
William A Smith, Houston, TX (US);
Mark A Mueller, Austin, TX (US);
Gregory B Demoll, LaGrange Park, IL (US);
Texaco Chemical Company, White Plains, NY (US);
Abstract
Impure propylene oxide is purified by a distillation process wherein it is (a) extractively distilled in a first column using a C.sub.2 to C.sub.6 alkylene glycol extractive distillation agent to form a first overhead fraction comprising propylene oxide, C.sub.5 -C.sub.7 hydrocarbons methanol, water and oxygen-containing impurities, (b) wherein the first overhead fraction is separated in a second column into a second overhead fraction comprising most of the pentanes, pentenes and oxygen-containing impurities and a partially purified propylene oxide bottoms fraction comprising propylene oxide, hexenes, hexanes, and only residual quantities of pentenes and pentanes, (c) wherein the partially purified bottoms fraction is extracting distilled in a third column using a C.sub.7 -C.sub.10 alkane hydrocarbon extractive distillation agent to provide a further purified bottoms fraction containing substantially all of the propylene oxide, hexenes, hexanes charged to the third distillation column, and (d) the further purified bottoms fraction is extractively distilled in a fourth column using a C.sub.7 to C.sub.10 alkane hydrocarbon extractive distillation agent to provide a purified propylene oxide overhead fraction consisting essentially of propylene oxide.