Abstract

In the treatment of tannery wastewater, other chemical agents such as tannins and fatliquors may possibly have an influence on bio-decolourization of dyes, few researchers have addressed that problem. This paper reports how four kinds of commercial fatliquors influence the bio-decolourization of an azo dye (Acid Fuchsin 6B as the experimental object) and expounds the mechanisms of these influence processes. It was obvious that the addition of sulfonated fatliquor and oxidized-sulfited fatliquor have improved the bio-decolourization activity of Acid Fuchsin 6B, by contrary, the biodecolourization of the dye has been stopped virtually by the addition of Lecithin based fatliquor and Phosphoric esters fatliquor. The paper used LC/MS to analyze and quantify metabolites of the dye in various substrates. The results certify that a stimulation of degradation products of these fatliquors on the breaking of the azo linkage contributes to the improvement of the bio-decolourization of the azo dye. And according to the correlation coefficient of the poly-β-hydroxybutyrate production with the residual concentrations of the dye, the inhibition of the fatliquors with phosphate groups on the biodecolourization is directly due to the formation of the poly-β-hydroxybutyrate.