The composition and mercury complexation characteristics of dissolved organic matter in landfill leachates with different ages.
Dissolved organic matter obtained from landfill leachate was separated into hydrophobic acid, base, neutral (HOA, HOB, HON) and hydrophilic (HIM) fractions. Fluorescence excitation-emission matrix spectra and parallel factor analysis were employed to characterize the composition, and fluorescence quenching titration technique was applied to study the complexation between Hg (II) and HON, HOA, and HIM fractions. Protein-like substances, humic-like compounds and xenobiotic organic matters (XOM) were identified in all fractions. The HOA, HOB and HON fractions comprised mainly XOM, while the HIM fraction consisted primarily of humic-like compounds. The complexation ability of protein-like substances was higher than that of humic-like compounds. The complexation ability of the HIM was highest for protein-like substances, while the complexation ability of the HON fraction was the highest for humic-like substances. The results suggested that the toxicity and bioavailability of the mercury in the young leachates was the highest, and decreased with landfill time.
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Bei-Dou
BD
Xi
Xiao-Song
XS
He
Zi-Min
ZM
Wei
Yong-Hai
YH
Jiang
Dan
D
Li
Hong-Wei
HW
Pan
Hong-Liang
HL
Liu
D001682:Biological Availability; D004784:Environmental Monitoring; D006812:Humic Substances / Q000032:analysis; D057927:Hydrophobic and Hydrophilic Interactions; D008628:Mercury / Q000032:analysis* / Q000737:chemistry* / Q000378:metabolism; D012037:Refuse Disposal; D013050:Spectrometry, Fluorescence; D013997:Time Factors; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000737:chemistry* / Q000378:metabolism
D006812:Humic Substances; D014874:Water Pollutants, Chemical; D008628:Mercury