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:
Jan. 11, 2005
Filed:
Feb. 24, 2003
Applicants:
Iikubo Yuichi, West Lafayette, IN (US);
Hae Seok Ji, Ulsan, KR;
Ook Jae Cho, Ulsan, KR;
Inventors:
Assignee:
Ulsan Chemical Co., Ltd., Ulsan, KR;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C07C 1700 ;
U.S. Cl.
CPC ...
Abstract
A method of producing difluoromethane (HFC-32), which includes firstly reacting methylene chloride with hydrogen fluoride in gas phase at 280 to 340° C. in the presence of a fluorination catalyst to produce chlorofluoro methane, and secondly reacting the chlorofluoro methane with hydrogen fluoride in liquid phase at 60 to 80° C. in the presence of an antimony chloride catalyst. The method is advantageous in that HFC-32 is produced in high yield under mild reaction conditions using a relatively small amount of energy.