Nano-ZnO film photocatalysts in bench-scale continuous-flow mineralization of olive mill waste contaminants in water, International Journal of Environmental Science and Technology, 2021, Issue date May 2022
Publication Type
Original research
Authors

Olive oil milling, widely practiced in Mediterranean countries, including Palestine, yields the so-called olive mill waste water (OMWW) or Zebar (Zibar). The waste contains minerals and organic materials (including phenols and polyphenols) which undergo continuous oxidation and cause environmental hazards if not well managed. This work basically aims at purifying surface waters, intentionally pre-contaminated with OMWW organic contaminants. Fate of other mineral ions present in the contaminated water is also investigated. ZnO nanoparticles, deposited as films onto glass reactor bottom (165 cm2 area), are described as catalyst for photodegradation of the organic contaminants, in a continuous flow reaction mode (gravity fed, typically at flow rate 3.5 mL/min). Two types of ZnO materials, namely commercial ZnO onto glass (C–ZnO/Glass) and synthetic ZnO supported onto clay and deposited on glass (Syn–ZnO/Clay/Glass), have been examined. The Syn–ZnO/Clay/Glass catalyst is slightly more efficient in removing organic contaminants (~ 43%), compared to the C–ZnO/Glass (41%) in 30 h. Different reaction parameters have been investigated, such as waste dilution factor, exposure duration, pH and catalyst recovery and reuse.

Journal
Title
International Journal of Environmental Science and Technology
Publisher
Springer
Publisher Country
United States of America
Indexing
Thomson Reuters
Impact Factor
2.54
Publication Type
Both (Printed and Online)
Volume
19
Year
2022
Pages
4379–4392