Removal of Styrene from Airflow by Photocatalytic Method Using Zinc Oxide Nanoparticles Stabilized on Diatomite

Styrene monomer is a volatile organic compound that is used extensively in the manufacture of plastics, rubber, and resins. Many health effects caused by continuous exposure to styrene have been reported by different organizations of health and safety. This study was carried out to determine the efficiency of photocatalytic removal of styrene by using zinc oxide nanoparticles immobilized on diatomite.

This study was done on a laboratory scale, in which zinc oxide nanoparticles with the size of 20 to 40 nm and 5% concentration were stabilized on the natural diatomite and then irradiated with UV light as a photocatalytic agent in order to degrade styrene vapors.

In this study, the concentrations of 20, 100, and 300 ppm styrene were passed through a reactor containing diatomite substrate covered with nano-ZnO (MDi/ZnO 5%). The results showed that the bed of MDi/ZnO 5% could remove 35 percent of styrene vapors at concentrations of 20 ppm and a flow rate of 1 lit /min.

Due to the removal efficiency of 35% styrene vapors by MDi/ZnO 5% substrate and properties such as low cost and availability of diatomite and zinc oxide, it can be used from the bed to remove volatile organic compounds, but in comparison to similar studies with other beds such as natural and synthetic zeolites and activated carbon, it could not achieve the desired results in a photocatalytic activity for its application in industry. However, because of its abundance in the world and Iran, low cost of preparation, and also its unique characteristics, further studies are recommended about its modification and application in photocatalytic processes.