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. 11, 1994
Filed:
Oct. 26, 1993
William K Culbreth, III, Beaumont, TX (US);
Yu-Hwa E Sheu, Hsinchu, TW;
David G Pottratz, Austin, TX (US);
Texaco Chemical Company, White Plains, NY (US);
Abstract
Contaminants are removed from impure propylene oxide by fractionating in a first column to remove overhead essentially all of the pentenes and pentanes and most of the oxygen-containing impurities to provide a partially purified first propylene oxide bottoms fraction, extractively distilling the first bottoms fraction in a second extractive column using a C.sub.2 to C.sub.6 alkylene glycol extractive distillation agent to form a second overhead fraction comprising propylene oxide, hexenes, hexanes, water, residual quantities of pentenes and pentanes and oxygen-containing impurities, extractively distilling the second overhead fraction in a third column using a C.sub.6 to C.sub.10 alkane hydrocarbon extractive distillation agent to form a third bottoms fraction comprising the extractive distillation agent, propylene oxide, hexenes, hexanes, residual quantities of pentenes and pentanes and water, and extractively distilling said third bottoms fraction in a fourth column using a C.sub.6 to C.sub.10 alkane hydrocarbon extractive distillation agent to form a fourth overhead fraction consisting essentially of propylene oxide.