Abstract
For the purpose of applying non-thermal plasma to the effective decomposition of volatile organic compounds (VOC) with low concentrations, experiments on the decomposition of acetaldehyde were conducted using a lab-scale non-thermal plasma reactor in which α-Al2O3 and BaTiO3 particles of 1.0mm average diameter were packed.
Results showed that an acetaldehyde decomposition ratio of more than 95% was obtained in the non-thermal plasma reactor packed with BaTiO3 particles at 10kV input voltage. CO and CO2 were detected as the main carbonaceous reaction products. Acetaldehyde was probably decomposed by electrons or activated species, resulting mostly in the production of CO2, which was partially decomposed to CO with increased input voltages. Results also showed that when water vapor pressure in the reaction gas was higher at a low input voltage, the decomposition of acetaldehyde was hindered, while the mineralization ratio of acetaldehyde and the selectivity of CO2 increased. This suggests that energy for acetaldehyde decomposition decreased because of a reaction between H2O and electrons to produce OH radicals. The intermediate products including CO were then more easily oxidized by the OH radicals, and the conversion of CO2 to CO was inhibited by decreased energy.
