| dc.description.abstract |
Volatile organic compounds (VOCs) have been widely used in industrial processes. Among them, trichloroethylene(TCE) is a solvent mainly used for metal degreasing and dry cleaning. However, it is toxic and probably causes cancer for humans. Perovskite-type catalysts such as LaMnO3 have been studied for VOC removal and they can be modified by partial substitution to enhance catalytic activity and mineralization rate. Also, non-thermal plasma (NTP) can effectively eliminate VOCs, because NTP can generate radicals to decompose and oxidize VOC molecules. However, NTP has several drawbacks such as low selectivity and O3 formation. In this study, removal of trichloroethylene (TCE) is investigated using a hybrid system which combines NTP and perovskite-type catalyst. The operating conditions are TCE = 150 ppm, applied voltage = 14 - 17 kV, frequency = 8 kHz, and gas flow rate = 500 mL/min. The removal efficiency of TCE achieved with the DBD plasma increases from 24% to 75% as applied voltage is increased from 14 to 17 kV, while mineralization rate is increased from 4% to 11%. For product analysis, phosgene (PG), dichloro acetyl chloride (DCAC), trichloroacetaldehyde (TCAD), O3, CO, and CO2 were mainly observed in the NTP process. As La0.8Ce0.2Mn0.8Ni0.2O3 is placed into the discharge zone to form the hybrid system, the removal efficiency of TCE achieved increases from 24% to 90% as the applied voltage is increased from 14 to 17 kV, while mineralization rate achieved with plasma catalysis reaches 41% at 17 kV. More importantly, the formation of the hazardous products such as O3, NOx, phosgene, and chlorine is significantly reduced as a perovskite-type catalyst is introduced. Overall, the preliminary results indicate that plasma catalysis can enhance the performance of catalyst for TCE removal. | en_US |