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.

Date of Patent:
Jun. 08, 2021

Filed:

Dec. 12, 2017
Applicant:

Hanwha Chemical Corporation, Seoul, KR;

Inventors:

Hyun Cheol Ryu, Daejeon, KR;

Kee Do Han, Daejeon, KR;

Seong Ho Park, Daejeon, KR;

Chang Mo Chung, Daejeon, KR;

Assignee:
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 263/20 (2006.01); B01D 3/00 (2006.01); B01D 3/14 (2006.01); B01D 3/32 (2006.01); B01D 5/00 (2006.01);
U.S. Cl.
CPC ...
C07C 263/20 (2013.01); B01D 3/009 (2013.01); B01D 3/141 (2013.01); B01D 3/322 (2013.01); B01D 5/006 (2013.01);
Abstract

The present invention relates to a toluene diisocyanate purification method enabling acquisition of a product having a small amount of dimers in a final product by means of using a reactive dividing wall column during toluene diisocyanate preparation. More particularly, according to the present invention, in order to obtain a product having a small amount of dimers in accordance with a reversible reaction of a monomer and a dimer, a purification procedure is designed by means of applying the temperature, pressure, time of stay and the like of a reactive dividing wall column as appropriate particular conditions, a reboiler having short time of stay and high heat transfer rate is used, and thus a dimerization reaction is inhibited and the purity and yield of the product are enhanced. Therefore, high-purity toluene diisocyanate can be purified and obtained.


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