Purification of Toluene vapor-Polluted Air by Photocatalytic-Adsorption Self-Cleaning Filter

Background and aim: Toluene is an organic compound with widespread applications. Due to its effects on human health, it must be controlled before discharging to the environment. Photocatalytic oxidation process is one of the environment-friendly and effective methods for the remove the organic compounds from the air which likely to be better in combination with other methods such as adsorption. This study is conducted with the aim at examining the effects of combination Activated carbon to Titanium dioxide on the toluene removal efficiency Material and Methods: In this study, to prepare photocatalytic bed, TiO2 and to prepare adsorption- photocatalytic bed, TiO2 and Activated carbon are fixed on the fiberglass by dip-coating method. The efficiency of the photocatalytic oxidation of toluene is evaluated in two separate reactors exposed to ultraviolet light. Additionally, to investigate the effect of initial concentration of toluene and airflow rate on the photocatalytic removal efficiency in photocatalytic and photocatalytic-adsorption beds, the RSM method was used to design experiments. Results: The results illustrate that the removal efficiency and elimination capacity of toluene in photocatalytic and photocatalytic-adsorption beds are Influenced by airflow rate and inlet concentration of toluene. In optimized operational conditions, the removal efficiency in both combined and non- combined reactors in inlet loadings of 84.5 and 1.65 mg/m3.s and retention time of 2 and 8.5 s, was 99.98% and 95.14%, respectively. Also, elimination capacity in optimized operational points in the two absorbent and non-absorbent photocatalysts was 5008.71 and 1204.85 mg/m3.min, respectively. Conclusion: self-cleaning photocatalyst had high efficiency in the present study and the use of photocatalytic-adsorption bed can as a suitable method with high removal efficiency causing adsorption and treatment of the pollutants. In other word, combination Activated carbon with Titanium dioxide improved the functionality of activity of photocatalytic oxidation through promoting adsorption sites and increasing residence time of the pollutant in the bed