MnO_x Nanoparticle-loaded polyacrylonitrile fibers for efficient catalytic ozonation of toluene

Catalytic ozonation stands out as a promising technology for volatile organic compounds (VOCs) degradation. Two polyacrylonitrile fiber-supported catalysts, MnOx/APANF and MnOx/CPANF, were synthesized by depositing MnOx nanoparticles onto amino-rich and carboxylic-rich fibers, respectively. The catalytic activity of these catalysts in toluene ozonation was systematically examined. MnOx/APANF exhibited superior catalytic activity compared to MnOx/CPANF, attributed to its higher Mn content, a greater Mn3+/Mn4+ ratio, and a more abundant alkaline microenvironment, achieved with the assistance of amino groups. MnOx/APANF achieved 100% toluene conversion at a relatively low temperature of 100 degrees C, with the production rate of dominant organic by-products at only 0.08% and 0.53% for MnOx/APANF and MnOx/CPANF, respectively. Notably, MnOx/APANF exhibited remarkable stability, maintaining the original toluene conversion efficiency for 660 min at 110 degrees C. The kinetic study, employing the power-law model, established the reaction order of toluene and ozone, along with the rate constant for the catalytic ozonation of toluene using MnOx/APANF. Remarkably, both the reaction order and rate constant demonstrated variations with changes in temperature. These PANF fiber-supported catalysts hold significant potential for a broad range of applications in low-temperature elimination of VOCs.