Abatement of Toluene in the Plasma-Driven Catalysis: Mechanism and Reaction Kinetics

The mechanism and reaction kinetics of toluene destruction in a plasma-driven catalysis (PDC) system were studied. The results show that the toluene removal efficiency (TRE) is greatly increased while the level of O₃ by-product is significantly reduced in PDC as compared with that in nonthermal plasma (NTP). The rate constant of toluene destruction in the PDC is more than twice than that in NTP. Among the multiple reactive species responsible for toluene destruction in the PDC, hydroxyl radicals (·OH) had a small contribution, whereas energetic electrons and atomic oxygen (O) were the most important. The enhanced performance of toluene destruction by PDC was mainly due to greater amounts of O formed during the process. The catalysts improved toluene destruction by catalytic decomposition of O₃ and generation of O. Essentially, better toluene abatement can be achieved by focusing on the increased energy density and improved performance of the catalyst for O₃ decomposition.