A method for the separation of 1,5 - dinitro anthraquinone and 1,8 - dinitro anthraquinone from dinitro - anthraquinone mixtures

摘要

The present invention relates to a process for separating substantially pure 1,5-dinitroanthraquinone and substantially pure 1,8-dinitroanthraquinone from anthraquinone dinitration mixtures containing 1,5- and 1,8-dinitroanthraquinone, whereby such mixtures are treated with a mixture of concentrated nitric acid and an inert organic solvent, the insoluble 1,5-dinitroanthraquinone is separated off and the 1,8-dinitroanthraquinone isolated from the remaining mother liquor.