Abstract: A method of purifying dinitroaniline of the general formula: ##STR1## in which: R is linear or branched C.sub.1 -C.sub.6 alkyl, C.sub.4 -C.sub.6 cycloalkyl, C.sub.1 -C.sub.4 monohaloalkyl or C.sub.1 -C.sub.4 alkoxy(C.sub.2 -C.sub.4)alkyl,Y is C.sub.1 -C.sub.4 alkyl, halogen or CF.sub.3, andX is hydrogen, halogen, C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, C.sub.1 -C.sub.4 monohaloalkyl, or C.sub.1 -C.sub.4 alkoxy(C.sub.1 -C.sub.4)alkyl, by N-denitration of the impurities of N-2,6-dinitroaniline contained therein, in the presence of a base selected from alkali-metal hydroxides, alkali-metal carbonates and ammonium hydroxide, at neutral or basic pH, comprising the treatment, with stirring, of the dinitroaniline to be purified, with an alcoholic organic solvent.

Abstract: A method for the purification of dinitroanilines having herbicidal activity by means of the known reactions of denitrosation using acid, and denitration in a neutral or basic environment in the presence of a phase-transfer catalyst, wherein:the denitrosation reaction is effected on the dinitration mixture containing the dinitroaniline of interest and the corresponding unwanted N-nitroso- and N-dinitroaniline impurities, and in the absence of solvent,the denitration reaction is conducted sequentially to the denitrosation reaction in the same reactor with the addition to the denitrosation product as such of an aqueous base, and of the said phase-transfer catalyst.