Toxicity and organic content characterization of olive oil mill wastewater undergoing a sequential treatment with fungi and photo-Fenton oxidation.
Olive oil mill wastewater (OOMW) is responsible for serious environmental problems. In this study, the efficiency of two treatments involving fungi and photo-Fenton oxidation, sequentially applied to OOMW was analyzed for organic compounds degradation and toxicity mitigation. The treatment with fungi (especially Pleurotus sajor caju) of diluted OOMW samples promoted a reduction of their acute toxicity to Daphnia longispina. Although this fungi species have not induced significant color reduction it was responsible for 72,91 and 77% reductions in chemical oxygen demand (COD), total phenolic and organic compound contents. After biological treatment, photo-Fenton oxidation seemed to be an interesting solution, especially for color reduction. However, the OOMWs remained highly toxic after photo-Fenton oxidation. Considering the second sequence of treatments, namely photo-Fenton oxidation followed by biological treatment, the former revealed, once more, a great potential because it can be applied to non-diluted OOMW, with significant reductions in COD (53-76%), total phenolic content (81-92%) and organic compounds content (100%). Despite fungal species still have demonstrated a high capacity for bioaccumulation of organic compounds, resulting from photo-Fenton oxidation, the biological treatment did not cause substantial benefits in terms of COD, total phenolic content and toxicity reduction.
Justino
Celine I
CI
ISEIT/Viseu, Instituto Piaget, Estrada do Alto do Gaio, Galifonge, 3515-776 Lordosa, Viseu, Portugal.
Duarte
Katia
K
Loureiro
Filipe
F
Pereira
Ruth
R
Antunes
Sara C
SC
Marques
Sérgio M
SM
Gonçalves
Fernando
F
Rocha-Santos
Teresa A P
TA
Freitas
Ana C
AC
D002244:Carbon; D019649:Food Industry; D005658:Fungi / Q000378:metabolism*; D006861:Hydrogen Peroxide; D007220:Industrial Waste / Q000517:prevention & control*; D007501:Iron; D000069463:Olive Oil; D010084:Oxidation-Reduction; D019800:Phenol; D055668:Photochemical Processes; D010938:Plant Oils; D020076:Pleurotus / Q000378:metabolism; D014873:Water Pollutants / Q000032:analysis* / Q000737:chemistry / Q000528:radiation effects / Q000633:toxicity*
C045076:Fenton's reagent; D007220:Industrial Waste; D000069463:Olive Oil; D010938:Plant Oils; D014873:Water Pollutants; D019800:Phenol; D002244:Carbon; D006861:Hydrogen Peroxide; D007501:Iron