Purification of polluted air from toluene vapor using catalytic oxidation and photocatalytic methods

Abstract

Abstract Introduction : Indoor air quality and it’s side effects have increased the prevalence of emerging diseases and cancer. Due to its widespread use in industrial products, Toluene is an organic solvent that has a high potential for release and various health effects. Various methods, including catalytic oxidation and photocatalytic oxidation, have been proposed to limit VOCs in indoor environments. One of the most effective and cost-effective catalysts used in air purification is manganese oxides (MnxOy), which are effective in converting organic compounds into water, carbon dioxide, and other low-risk compounds at room temperature. Photocatalytic oxidation of pollutants is also economically and environmentally popular. Material and methods The aim of this study was compared the efficiency of catalytic oxidation and photocatalytic removal of toluene from polluted air at room temperature on aluminum mesh in a glass reactor with dimensions of 20 cm height, 7 cm outer diameter, and 6 cm inner diameter. After preparing the surface of the used beds, the airflow containing pollutants was introduced into the beds, and the concentration of toluene was measured before and after of pass through from bed surface. The results were analyzed using descriptive statistics, one-way analysis of variance, and efficiency and capacity equations. Results The results showed a reduction in toluene concentration by catalytic and photocatalytic methods at room temperature. The photocatalytic reactor had better removal efficiency at a high flow rate (5.45 L/min) and low concentration (4.27 ppm), while MnO2 had better performance at a medium concentration (13.87 ppm) and flow rate (3.30 L/min), and KMnO4 had better performance at high concentration (44.28 ppm) and flow rate (5.48 L/min). Conclusion Catalytic oxidation and photocatalytic methods have suitable efficiency and capability for removing volatile organic compounds at low concentrations that we mainly face in indoor environments. We can choose the desired surface area for catalytic or photocatalytic beds depending on the pollutant concentration and flow rate.