Organic compounds -- part of the class 532-570 series – Organic compounds – Heterocyclic carbon compounds containing a hetero ring...
Patent
1994-06-01
1996-02-20
Tsang, Cecilia
Organic compounds -- part of the class 532-570 series
Organic compounds
Heterocyclic carbon compounds containing a hetero ring...
C07D30789
Patent
active
054930332
ABSTRACT:
In the purification of crude tetrachlorophthalic anhydride containing hexachlorobenzene as impurities, this invention relates to purification by decomposition in which crude tetrachlorophthalic anhydride is contacted with chlorine gas in fuming sulfuric acid or sulfuric anhydride in the presence of iodine or iodine trichloride to decompose the impurities and remove them or purification by washing in which hexachlorobenzene is separated by washing with a chlorinated solvent. This invention also relates to a process for purifying crude tetrachlorophthalic anhydride containing iodotrichlorophthalic anhydrides as impurities by applying a radical reaction treatment in a chlorinated solvent to convert iodotrichlorophthalic anhydrides to tetrachlorophthalic anhydride. Moreover, it relates to high-purity tetrachlorophthalic anhydride containing 10 ppm or less of hexachlorobenzene. With the process of this invention, it is possible to recover high-purity tetrachlorophthalic anhydride with extremely low contents of impurities readily in high yield.
REFERENCES:
patent: 2429985 (1947-11-01), Blume et al.
patent: 2460564 (1949-02-01), Amacker
patent: 2460565 (1949-02-01), Amacker
patent: 2547504 (1951-04-01), Steahly
patent: 2547505 (1951-04-01), Steahly
patent: 3007943 (1961-11-01), Hoffmann
"Monthly Journal of Chemistry and Related Areas of Other Sciences", vol. 64, Aug. 1934.
"Studies of Chlorination, Principally to Obtain Tetrachlorophthalic Anhydride, Pentachlorobenzoic Acid and a New (Tetrachlorophenyl)Trichloromethane", Chemical Abstracts, vol. 45, No. 2, 1951.
"The Synthesis of Tetrachlorophthalic Anhydride" Chemical Abstracts, vol. 55, No. 2, 1961.
Maekawa Seiji
Tomita Kyoichi
Ueda Zentaro
Nippon Light Metal Company Ltd.
Tsang Cecilia
LandOfFree
Process for purifying tetrachlorophthalic anhydride does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for purifying tetrachlorophthalic anhydride, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for purifying tetrachlorophthalic anhydride will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1357117