| abstract |
A METHOD FOR OBTAINING SULFUR ACID PASTE 1,5-DIOXI-2,6-DISUL-FOANTRAHINON, as indicated by the fact that the reaction mixture obtained after sulfonation of a mixture of 1,5 and 1,8-dioxyanthraquinone or the corresponding mixture dimethoxyanthraquinone with concentrated sulfuric acid, treated with water to a sulfuric acid concentration of 80-90% at 50-70 0, followed by filtration of the target product by cooling to 15-25 ° C and washing with 80-90% sulfuric acid. |