The dyeing agate employs large quantities of potentially harmful wastewater to the environment, such as, effluent with chromium and nitrate ions. The aim of the present study was investigate the electrodialysis technique efficiency in the removal of contaminant ions present in wastewater generated by the agate dyeing industry and evaluate the toxicity of the effluent studied. The electrodialysis experiments were performed in acrylic cell 5 compartments separated by ion selective membranes and fitted with a 70TiO2/30RuO2 DSA® anode and a titanium plate as cathode. After application of the electrodialysis treatment, toxicity of the effluent was evaluated in two different trophic levels, Artemia salina and Lactuca sativa. The results indicated the removal of 233.3 mg L-1 of nitrate and 223.6 mg L-1 of chromium was extracted, in flow mode. The toxicity tests showed a tendency to decrease the percentage of mortality of organisms after application of the electrodialysis technique. Thus, it concludes that the electrodialysis is an effective method for treating effluents containing metal ions, and is possible reuse the recovered solutions in the dyeing process.
Keywords:
electrodialysis; wastewater treatment; toxicity; clean technologies
