Chemical Degradation of EDTA and DTPA in a Totally Chlorine Free (TCF) Effluent Available to Purchase

In this work, a synthetic TCF effluent containing vanillin, glyoxal, sodium formate, sodium acetate and the chelanting agents EDTA and DTPA was treated using, O₃, O₃/H₂O₂, O₃/UV, UV, UV/H₂O₂ and UV/H₂O₂/O₃ at pH 7 and 11. The best results were obtained in the O₃/UV process. Ozone alone did not degrade EDTA neither DTPA. A combined O₃/UV (pH 7.0 by 15 min)-biological treatment was very efficient in the removal of the chelants (98 %) and COD (95 %).