title: Treatment of olive mill wastewater by photooxidation with ZrO2-doped TiO2 nanocomposite and its reuse capability.
abstract: Zirconium dioxide (zirconia, ZrO2)-doped TiO2 (TiO2/ZrO2) nanocomposite was used for the photocatalytic oxidation of pollutant parameters [COD components (CODtotal, CODdissolved and CODinert)], polyphenols (catechol, 3-hydroxybenzoic acid, tyrosol and 4-hydroxybenzoic acid) and total polyaromatic amines [aniline, 4-nitroaniline, o-toluidine and o-anisidine] from the olive mill effluent wastewaters at different operational conditions such as at different mass ratios of ZrO2 (50, 25, 14, 10 and 5 wt%) in the TiO2/ZrO2 nanocomposite, at different TiO2/ZrO2 photocatalyst concentrations (1, 4, 15 and 50 mg/L) and pH values (4.0-7.0-10.0) under 300 W UV irradiations, respectively. Under the optimized conditions (pH = 4.6, 15 mg/L ZrO2/TiO2 nanocomposite with a ZrO2 mass ratio of 14 wt%, 300 W UV light, after 60 min photooxidation time, at 21°C), the maximum CODdissolved, total phenol and total aromatic amines photooxidation yields were 99%, 89% and 95%, respectively. High pollutant removal (89%) yields after sequential five times utilization of ZrO2/TiO2 nanocomposite show that this catalyst can be effectively used commercially in the treatment of olive mill effluent.
authors.affiliation: a Department of Environmental Engineering, Engineering Faculty , Dokuz Eylül University , Tınaztepe Campus, 35160 Buca/İzmir , Turkey.
authors.forename: Delia Teresa
authors.initials: DT
authors.lastname: Sponza
authors.affiliation: a Department of Environmental Engineering, Engineering Faculty , Dokuz Eylül University , Tınaztepe Campus, 35160 Buca/İzmir , Turkey.
authors.forename: Rukiye
authors.initials: R
authors.lastname: Oztekin
mesh_terms: D000383:Agriculture; D007220:Industrial Waste; D053761:Nanocomposites / Q000737:chemistry*; D031658:Olea / Q000737:chemistry*; D010636:Phenols / Q000032:analysis / Q000737:chemistry; D055668:Photochemical Processes; D014025:Titanium / Q000737:chemistry*; D062065:Wastewater / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D007220:Industrial Waste; D010636:Phenols; D014025:Titanium; D062065:Wastewater; D015040:Zirconium; C009495:titanium dioxide; C028541:zirconium oxide
keywords: Zirconium-doped titanium dioxide nanocomposite; olive mill effluent wastewater; photooxidation; polyaromatic amines; polyphenols