Photocatalytic Removal of Methylbenzene Vapors by MnO2/Al2O3/Fe2O3 Nano composite

Maryam Feiz-Arefi, Farshid Ghorbani-Shahna, Abdulrahman Bahrami, Hossein Ebrahimi, Alireza Mahjub


Methyl benzene, which has carcinogenic effects, is a volatile organic compound that is widely used in various industries. Nano composites of Mno2/Al203/Fe203, which is a new photocatalyst, have not been applied to remove contaminants from air streams. Therefore, the aim of the present study was to investigate the photocatalytic removal of ethyl benzene by using this nano composite activated by visible light. Morphological characteristics of the synthesized Nano composite in a sol-gel method are determined through XRD, FTIR, and SEM. Through the photocatalyst process and by the use of visible light radiation, the synthesized Nano composite is used to degrade ethyl benzene in the gas phase. In order to estimate the main effects and interaction ones and to optimize the experiment numbers, the response surface method was used. Operational parameters investigated in the study are the initial concentration of contaminants, relative humidity, and the residence time, which were considered in three levels; further, the experiments were designed by Design Expert version 9 software. The results show the Nano composite particle sizes were less than 82 nanometers. The findings also indicate that relative humidity and residence time were effective parameters in removal efficiency of ethyl benzene. This Nano composite, at the optimal conditions, was capable of removing 98.72% of the pollutants, with an initial content of 300 ppm. MnO2/Al2O3/Fe2O3 Nano composite is a suitable catalyst to remove ethyl benzene from air streams. Among the features of the Nano composite are reaction at room temperature and lower production dangerous byproducts, which are the main advantages of this Nano composite as compared with other nano composites.


Nano-Composite, Ethyl benzene, Photocatalyst, MnO2/Al2O3/Fe2O3

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Iranian Journal of Health, Safety and Environment e-ISSN: :2345-5535 Iran university of Medical sciences, Tehran, Iran