Treatment of wastewaters from the olive mill industry by sonication

Abstract

AbstractBACKGROUND: In this study, the effects of additives (manganese (III) oxide (Mn3O4), Cu+2, Fe0 and potassium iodate (KIO3)) and radical scavengers (sodium carbonate (Na2CO3), perfluorohexane (C6F14) and t‐buthyl alcohol (C4H10O)) on the dephenolization, decolorization, dearomatization and detoxification of olive mill wastewater (OMW) by sonication were investigated because wastewaters from this industry are not removed effectively.RESULTS: The maximum COD, color, total phenol and total aromatic amines (TAAs) removal efficiencies were 63, 82, 78 and 71%, respectively, at 60 °C with sonication only. The TAAs and phenol yields were increased to 96 and 97% with 6 mg L−1 KIO3 and 3 mg L−1 Fe0 while color removal reached 97% with 6 mg L−1 C6F14. The total annual cost with sonication only was 665 € m−3 year−1 while the cost slightly increased (666€ m3 year−1) with C6F14. The maximum acute toxicity removals were 97‐98% in Daphnia magna and Vibrio fischeri The Microtox acute toxicity test was more sensitive than the Daphnia magna to the OMW samples.CONCLUSION: COD, color, total phenol, TAAs and toxicity in an OMW were removed efficiently and cost‐effectively by sonication. © 2012 Society of Chemical Industry