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:
Jul. 11, 1989
Filed:
Nov. 18, 1987
Jen-Tau Gu, Yuan-Ho, TW;
China Technical Consultants, Inc., Taipei, TW;
Abstract
A process for recrystallization of a brominated aromatic compound under pressure for purifying it from the contamination by bromine and hydrogen bromide, comprising the steps of: placing the brominated aromatic compound in a solvent or a combination of solvents selected from toluene, 1,dibromoethane, m-xylene, benzene, dichloromethane, chloroform, and 1,2-dichloroethane; adding into the resultant mixture a base or a combination of bases selected from pyridine, ethylene diamine, n-butylamine, tert-butylamaine, triethylamine, sodium ethoxide, sodium hydroxide, potassium hydroxide, sodium carbonate, and sodium bicarbonate; and heating the resultant mixture to a temperature above the atmospheric boiling point and at a pressure above the vapor pressure of the resultant material at that temperature.