Utilization of Hematite Particles for Economical Removal of o-xylene in a High-Temperature Gas-Solid Reactor

To establish a novel approach for VOCs resource utilization, coupled o-xylene oxidation and hematite reduction was investigated in this study in a high-temperature gas-solid reactor in the temperature range 300–700 °C. As the o-xylene-containing inert gas (N(2)) stream traveled through the hematite particle bed, its reaction behavior was determined in programmed heating and constant temperature modes. Consequently, the effect of bed temperature, flow rate and o-xylene inlet concentration on both o-xylene removal performance and degree of hematite reduction was studied. The raw hematite and solid products were analyzed by TGA, XRF, XRD and SEM-EDS. The results showed that a temperature above 300 °C was required to completely eliminate o-xylene by hematite, and both o-xylene removal capacity and degree of hematite reduction at 5% breakthrough points enhanced on increasing the temperature and decreasing the flow rate. The increment in temperature from 300 °C to 700 °C led to a gradual reduction of Fe(2)O(3) to Fe(3)O(4), FeO and metallic iron. Thus, this study provides a novel, economic and promising technology for treating the VOC pollutants.