Toluene Vapors Removal Using Cold Plasma and HZSM-5/TiO2 Photo Catalyst

Introduction: Regarding the daily growth of Volatile Organic Compounds (VOCs) application in a vast variety of industries which also contributed to their adverse effects, different methods were used for controlling their emission. One of the most effective methods for this purpose, is a combination of cold plasma and catalyst or photo catalyst. In this study, the effectiveness of the HZSM-5/ Tio2 for Toluene treatment removal was investigated Material and Methods: HZSM-5 zeolite, and Tio2 in 3 and 8 weight percent were used for photo catalyst preparation. The TiO2 particles were coated on the zeolite by impregnation method. X-Ray Diffraction, Scanning Electron Microscope and Brunauer Emmett Teller tests were used for the identification of photo catalyst structural properties. Toluene vapors with 58±2 PPM concentrations were produced in ambient condition including the room pressure and temperature by a dynamic system and introduced to a reactor included 1 gr of the photo catalyst. Vapors were passed from the reactor continuously with a rate of 0.5 liter per minute. Removal efficiency in three different states; plasma only, plasma /HZSM-5/TiO2 3%tw, and plasma/HZSM-5/TiO2 8% tw were assessed at the voltages of 4000 to 8000. Results: In the current study, the removal efficiency of toluene vapors were 44.9, 75.36 and 66.68 percent for plasma, plasma /HZSM-5/TiO2 3%tw and plasma/HZSM-5/TiO2 8% tw, respectively. Photo catalyst with 3 weight percent showed the best removal efficiency. In all tests, the removal efficiency increased when the voltage increased and in 7000 volts it reached the maximum level. Therefore, adding photo catalyst to the plasma caused significant improvement in removal efficiency. Also, HZSM-5/TiO2 3% tw showed the best performance for toluene vapors removal. Conclusion: According to the current study findings, using this combination in an industrial environment can be an effective way for Toluene vapors without the need for high temperatures. This combination can be proposed for other VOCs.