Abstract:Catalytic oxidation of low-concentration benzene, toluene and p-xylene (BTX mixture) with ozone over MnOx/Al2O3 catalyst was investigated in a fixed-bed flow reactor at room temperature. MnOx/Al2O3 catalyst significantly promoted decomposition of O3 and ozonation of low-concentration BTX. The optimal Mn loading amount was 5%. With inlet O3 and BTX concentration maintained at 70 and 15 mg/m3, the conversions of benzene, toluene, p-xylene and O3 reached 75%, 84%, 88% and 90%, respectively. The BTX conversion firstly increased and then leveled off with the increase of inlet O3 concentration, while the O3 conversion slightly decreased. The conversions of both BTX and O3 decreased with the increase of inlet BTX concentration. Catalyst deactivation occured as the reaction proceeded, which can be attributed to the buildup of organic intermediates such as aromatic aldehyde, aromatic acid and formic acid over catalyst surface during the catalytic oxidation process.