Treatment of olive mill wastewater by photooxidation with ZrO2-doped TiO2 nanocomposite and its reuse capability


SPONZA D. T., Oztekin R.

ENVIRONMENTAL TECHNOLOGY, vol.37, no.7, pp.865-879, 2016 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 37 Issue: 7
  • Publication Date: 2016
  • Doi Number: 10.1080/09593330.2015.1088579
  • Journal Name: ENVIRONMENTAL TECHNOLOGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.865-879
  • Keywords: polyphenols, polyaromatic amines, photooxidation, olive mill effluent wastewater, Zirconium-doped titanium dioxide nanocomposite, PHOTOCATALYTIC DEGRADATION, PHENOLIC-COMPOUNDS, ELECTRON-TRANSFER, ZIRCONIUM, TITANIA, PHOTODEGRADATION, BIODEGRADATION, SEPARATION, STABILITY, TIO2/SIO2
  • Dokuz Eylül University Affiliated: Yes

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 degrees 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.