Photocatalytic Decomposition of Ethylbenzene in Air using TiO2 Nano-catalysts in an Annular Photoreactor

Document Type: Research Article


1 School of Chemical Engineering, College of Engineering, University of Tehran, Tehran, Iran.

2 Microbiology and Biotechnology Group, Environment and Biotechnology Research Division, Research Institute of Petroleum Industry, Tehran, Iran.

3 Ecology and Environmental Pollution Control Research Group, Environment and Biotechnology Research Division, Research Institute of Petroleum Industry, Tehran, Iran.


The contaminated environment by various pollutants in the last decades is a serious concern for the governments and human societies all over the world. Volatile Organic Compounds (VOCs), emitted from a wide range of industries, are among such pollutants which can easily move in the air due to their volatile nature and are toxic and harmful to the environment and human health. Removal of gaseous ethylbenzene as an aromatic VOC using photocatalytic oxidation in an annular photoreactor packed with TiO2 nanoparticle-coated glass beads has been investigated in this research. The TiO2 nano-catalysts were characterized by XRD and FE-SEM. The removal efficiencies of about 75-100% could be yielded for the initial ethylbenzene concentrations up to 0.6 g/m3 in the UV irradiated reactor at a relatively low residence time. The inlet flow rate and initial ethylbenzene concentration were effective parameters on the removal efficiency and their increase caused reduction of removal efficiency. CO2 production in the photoreactor showed the mineralization of the pollutant during photocatalytic decomposition of ethylbenzene.


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