Background

Mono aromatic hydrocarbons (BTEX) are a group of hazardous pollutants which originate from sources such as refineries, gas, and oil extraction fields, petrochemicals and paint and glue industries.

Conventional methods, including incineration, condensation, adsorption and absorption have been used for removal of VOCs. None of these methods is economical for removal of pollutants of polluted air with low to moderate concentrations. The heterogeneous photocatalytic processes involve the chemical reactions to convert pollutant to carbon dioxide and water. The aim of this paper is a comparison of Benzene & Toluene removal from synthetic polluted air using a Nano photocatalytic TiO₂/ ZNO process.

Results

The X-ray diffraction (XRD) patterns showed that Nano crystals of TiO₂ and ZNO were in anatase and rutile phases. Toluene & benzene were decomposed by TiO₂/ ZNO Nano photocatalyst and UV radiation. Kruskal-wallis Test demonstrated that there are significant differences (p_value < 0.05) between pollutant concentrations in different operational conditions.

Conclusions

Degradation of toluene & benzene increases with increasing UV intensity and decreasing initial concentrations. Effect of TiO₂/ZNO Nano photocatalyst on benzene is less than that on toluene. In this research, Toluene & benzene removal by TiO₂/ZNO and UV followed first-order reactions.