The Performance Of Prepared Catalysts For Ozoni-zation Of Dyeing Effluents And Reusing Of Dyeing Effluents

Since discharge limits are becoming stricter for industry wastes, textile manufacturers are searching efficient and economical methods of pollution reduction. This is the typical situation facing the textile industry. Dyeing is an important process in textile industry. However dyeing wastewaters are known to be highly resistant to biodegradation under both natural and wastewater treatment plant conditions, especially as the wide using of PVA and surfactants in dyeing process. The urgent problem in conventional treatments is the removal efficiency of color and COD.Ozone treatment to remove color from wastewater could be a solution to the problem of color pollution. However COD removal is still low, and for the unstablity of ozone, there still need to increase the utility of ozone.In this paper, catalytic ozonization of dyeing effluents was studied. Among the selected transition metal oxides, it is indicated that nickelous oxide (NiO) is the most effective catalyst for the decolorizing and COD reducing of dyeing effluents. The finds also indicate that organics and ozone can be removed in activated charcoal adsorption after ozonization, and color reproducibility of the dyeings was excellent in recycling decolorized dyebath.