Degradation of pyrene in contaminated soil by the dielectric barrier discharge combined with the MnFe2O4 catalyst

Abstract

In this work, a spinel oxide of MnFe₂O₄ was used as the dielectric barrier discharge (DBD) catalyst for the remediation of pyrene-contaminated soil. The performances were investigated through tuning voltage, frequency, catalyst dosage, and soil moisture. Under the optimal conditions, such as the voltage of 10.0 kV, the discharge frequency of 1.0 kHz, MnFe₂O₄ dosage of 0.3 g, air flow rate of 2.0 L min⁻¹, soil humidity of 5.3%, and degradation efficiency of DBD/MnFe₂O₄ for pyrene could reach 79.26% after 10 min treatment, which was much higher than that of DBD for pyrene of 42.56%. The DBD/MnFe₂O₄ system also showed the high degradation efficiency of other pollutants including phenanthrene, p-nitrophenol, and p-nitrophenol in contaminated soil. The enhancing mechanism of the DBD/MnFe₂O₄ system was discussed.