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. 24, 2015
Filed:
Jun. 16, 2014
Asahi Glass Company, Limited, Chiyoda-ku, JP;
Satoshi Kawaguchi, Tokyo, JP;
Hirokazu Takagi, Tokyo, JP;
Masaaki Tsuzaki, Tokyo, JP;
Masato Fukushima, Tokyo, JP;
Hidekazu Okamoto, Tokyo, JP;
ASAHI GLASS COMPANY, LIMITED, Chiyoda-ku, JP;
Abstract
There is provided a method and an apparatus for efficiently obtaining 2,3,3,3-tetrafluoropropene with low contents of both organic impurities and water. The method for continuously purifying crude 2,3,3,3-tetrafluoropropene containing water and one or more organic impurities, the method including using an apparatus having a distillation column with X stages (3≦X, the stage closest to a column top is the first stage) and a unit for cooling and condensing a distillate; supplying the crude 2,3,3,3-tetrafluoropropene to an m-th stage (n+1≦m≦X, 2≦n≦X−1) of the distillation column, recirculating at least part of the distillate cooled and condensed in the unit for cooling and condensing to an h-th stage (1≦h≦n−1) of the distillation column; and taking out a liquid phase part of an n-th stage of the distillation column to obtain a purified product of 2,3,3,3-tetrafluoropropene.