Additive Effect on Energy Efficiency and Byproduct Distribution in VOC Decomposition with Nonthermal Plasma

In the decomposition of methanol, dichloromethane, toluene, and their binary mixtures with nonthermal plasma in N₂, the energy efficiency for the decomposition of each volatile organic compound (VOC) increased with its initial concentration. The addition of oxygen increased the maximum energy efficiency and the corresponding reactor energy density decreased with an increase in the oxygen content. On the other hand, it was not affected by 100 ppm of the counterpart VOC. Based on the byproduct analysis, the major pathways for their decomposition were determined. 5% O₂ in the reaction gases suppressed the formation of hydrocarbons ascribed to self-decomposition of VOCs, nitrogen atom incorporation into fragment radicals, and their cross-coupling.