Process for purifying propylene oxide

• US 6,736,941 B2
• Filed: 10/24/2002
• Issued: 05/18/2004
• Est. Priority Date: 04/28/2000
• Status: Expired due to Fees

• Current Assignee: Sumitomo Chemical Company Limited
• Original Assignee: Sumitomo Chemical Company Limited
• Inventors: Ishino, Masaru, Oku, Noriaki
• Primary Examiner(s): Manoharan, Virginia
• Application Number:
  US10/258,411
• Publication Number:
  US 20030102206A1
• Time in Patent Office: 572 Days
• Field of Search: 203/68, 203/69, 203/70, 203/100, 549/541
• US Class Current: 203/68
• CPC Class Codes: C07D 301/32 Separation; Purification

Abstract

A process is described for purifying propylene oxide, which includes the step of distilling propylene oxide containing impurities in the presence of a hydrocarbon having 5 carbon atoms or less. According to the present invention, a process is provided for purifying propylene oxide which has a feature that impurities contained in a solution containing propylene oxide to be purified can be efficiently removed. Oxygen-containing impurities, in particular, can be very efficiently removed.

Claims

1. A process for purifying propylene oxide, which consists essentially of distilling propylene oxide containing 50 ppm by weight to 5% by weight of oxygen-containing impurities in total in the presence of a hydrocarbon having 5 carbon atoms or less using a distillation column, discharging the oxygen-containing impurities together with the hydrocarbon from the top of the column, and recovering purified propylene oxide from the bottom of the column.

2. The process according to claim 1, wherein the hydrocarbon is a member selected from the group consisting of hydrocarbons having 3, 4, and 5 carbon atoms.

3. The process according to claim 2, wherein the hydrocarbon is a member selected from the group consisting of hydrocarbons having 4 and 5 carbon atoms.