Degradation of anthraquinone dyes by ozone

The decolorization of three kinds of anthraquinone dyes by ozone was investigated and the residues in the degradation solution were analyzed. The results indicate that the decolorizing effects are obvious with the decolorization efficiency of dyes all above 96% in 40 min. The pH value and TOC concentration decline while the conductivity increases with the lapse of reaction time. The complicated dye molecules are decomposed to simple compounds with —SO3H, —Cl in the dye molecules transformed into SO2-4, Cl-, and nitrogen partially degrades into NO-3 according to the bases of different groups. The organic acids are found in the degradation solutions and dyes with larger relative molecular mass are decomposed into substances with larger relative molecular mass.