Removal of low-concentration BTX in air using a combined plasma catalysis system

The behavior of non-thermal plasma (NTP) and combined plasma catalysis (CPC) was investigated for removal of low-concentration benzene, toluene and p-xylene (BTX mixture) in air using a link tooth wheel-cylinder plasma reactor. Combining NTP with MnOx/Al2O3 catalyst after the discharge zone (CPC) significantly promoted BTX conversion and improved the energy efficiency. For a specific input energy (SIE) of 10 J L−1, the conversion of benzene, toluene and p-xylene reached 94%, 97% and 95%, respectively. The introduction of MnOx/Al2O3 catalyst also moved the BTX conversion towards total oxidation and reduced the emission of O3 and NO2 as compared to NTP alone. For an SIE of 10 J L−1, the O3 outlet concentration decreased from 46.7 for NTP alone to 1.9 ppm for CPC, while the NO2 emission correspondingly decreased from 1380 to 40 ppb.