Continuous flow photodegradation of olive Zebar contaminants with simulated solar light using supported ZnO nanoparticles
Mohammad Ibrahim Nassar, Ibrahim
An Najah National University
Photocatalysis and adsorption are of the modern methods for water purification from biological and chemical pollutants. Photocatalysis is based on the presence of a catalyst (Zinc oxide) that absorbs ultraviolet radiation to destroy the contaminant substances (phenolic compounds). Researchers have developed several systems that increase the effectiveness of this catalyst in destroying organic pollutants and thus enable the use of direct sunlight in photo-driven water purification. The continuous flow system is designed to allow Zebar water (contaminated with phenols) to run continuously over the catalytic surface while exposed to radiation. There is an entrance connected to the glass container, on which the catalyst is installed. On the other hand, there is an outlet for the treated water to be collected in another container for the necessary tests. The properties of the glass-based catalyst were examined using electronic microscopy (SEM) and X-ray diffraction (XRD). The treated waters were analyzed using UV-Visible spectrophotometer, TOC and high-performance liquid chromatography (HPLC). In this study, photodegradation of organic compounds in Zebar water, that result from olive mills, was investigated using the zinc oxide nanoparticle films installed on the bottom of a glass container. Zinc oxide, supported onto natural clay particles, was also installed on the glass. Zebar water was passed over the catalyst film under simulated sunlight for photodegradation purposes. Effects of different parameters on photocatalytic process were studied including Zebar dilution, time duration, and pH. In the case of ZnO/glass catalyst, 40.8% of organic contaminants disappeared in 30 h, while in the case of ZnO/clay/glass 42.5% of organic contaminants disappeared. The supported catalyst was reused for several times. It showed no significant efficiency lowering after multiple uses. The results show the feasibility of using ZnO catalyzed photodegradation process in reclaiming water from Zebar. The The supported catalyst was reused for several times. It showed no significant efficiency lowering after multiple uses. The results show the feasibility of using ZnO catalyzed photodegradation process in reclaiming water from Zebar. The resulting water could be considered for agricultural use as it contains useful minerals.