[Spectroscopy properties of dissolved organic matter in landfill leachate during corrosion cell-Fenton post-treatment].

To differentiate the transformation of dissolved organic matter (DOM) during corrosion cell-Fenton (CCF) post-treatment, the leachate was separated into five fractions by XAD-8 and XAD-4 resins (hydrophilic fraction, HPI; hydrophobic acid, HPO-A; transphilic acid, TPI-A; hydrophobic neutral, HPO-N; transphilic neutral, TPI-N). UV-Vis spectroscopy and fluorescence spectroscopy were used for the degradation analysis. Experimental results showed that DOM in landfill leachate reduced 61.8% of dissolved organic carbon (DOC). Especially for HPO-A and HPO-N, with the removal ratios were up to 74.9% and 66.5%, respectively. The predominant portion in the effluent was HPI (comprising 60.1% of DOC). Spectral analyses showed that the leachate DOM was composed of abundant condensed ring aromatic compounds and humic substances, with the HPO-A was the highest aromatic fraction. The ratio of absorbance at 253 nm and 203 nm (E253/E203) was decreased in the order of HPO-A > HPO-N > TPI-A > TPI-N > HPI. The unsaturated conjugated structures were efficiently destroyed after the CCF treatment, and the functional groups such as carbonyl, amine were also eliminated. The main fluorophores in leachate fractions were in the region of aromatic protein-like and visible fulvic-like. The fluorescence intensity of peaks in each fraction decreased after CCF treatment, especially for the fulvic-like fluorescent substances. The results indicated that the CCF treatment was efficient to remove the hydrophobic fractions and reduce the complicacy of leachate effluent.