Document Type and Number:
Japanese Patent JPS561290
Kind Code:
B1
Abstract:
1385368 Nitration process SANDOZ Ltd 27 April 1972 [30 April 1971] 19620/72 Heading C2C A nitration process using concentrated HNO 3 is characterized by adding dilute HNO 3 to reduce the rate of reaction, the amounts of concentrated and dilute HNO 3 used being such that the HNO 3 concentration of the residual acid solution is greater than at the azeotropic point of said solution, the residual acid solution subsequently being fractionated into a concentrated HNO 3 fraction and a dilute HNO 3 fraction. The process is preferably effected continuously with the concentrated and dilute HNO 3 fractions being recycled. Water produced during the reaction may be removed as dilute HNO 3 and supplementary amounts of concentrated HNO 3 may be added to the concentrated HNO 3 cycle. Preferably, the concentrated HNO 3 is at least 90%, the dilute HNO 3 has a concentration of 70 to 80% and the HNO 3 concentration of the residual acid solution is 75 to 90%. In the examples, anthraquinone is nitrated to form mainly mononitroanthraquinones together with a minor amount of dinitroanthraquinones.
More Like This:
Application Number:
JP4141272A
Publication Date:
January 13, 1981
Filing Date:
April 26, 1972
Export Citation:
International Classes:
C07B43/02; C07C201/08; C07C205/47; (IPC1-7): C07B11/00
Next Patent: BOTH-SIDE RECORDING METHOD AND DEVICE