Degradation of refractory organics in biotreated landfill leachate using high voltage pulsed discharge combined with TiO2

摘要

The effect of high voltage pulsed discharge (HVPD) combined with TiO2 on the degradation of refractory organic compounds in actual biotreated landfill leachate was investigated. The optimal chemical oxygen demand (COD) removal efficiency could achieve to 58.9% using HVPD + TiO2 within 30 min at 40 kV, 400 Hz, and the conductivity of 4.05 ms cm(-1) in gas-liquid pulsed discharge. The aromatic compounds decreased by 33.6% compared with HVPD alone according to the UV absorbance at 254 nm. Moreover, the fluorescence intensity of humic and fulvic substances was greatly decreased. Active species such as center dot OH radical and H2O2 were enhanced in the presence of TiO2, resulting in more high molecular weight organic matter into small molecules or mineralized. In addition, possible degradation pathways was proposed based on acetophenone, which is effective for the degradation of organic matter in biotreated landfill leachate as long as the active species increased. (C) 2016 Elsevier B.V. All rights reserved.