title: Spectroscopic studies of the effect of aerobic conditions on the chemical characteristics of humic acid in landfill leachate and its implication for the environment.
abstract: Humic acids (HAs) that extracted from leachates from semi-aerobic and anaerobic landfills test field at different stabilization times were characterized by elemental composition, Fourier transform infrared spectroscopy (FTIR), and Carbon-13 Cross-Polarization Magic-Angle-Spinning Nuclear Magnetic Resonance ((13)C CP/MAS NMR). The higher sulfur (S) content of HA in the anaerobic landfill leachate after a short stabilization time showed that the S released from the organic matter degradation was more easily stabilized under anaerobic conditions, which indicate that HA from anaerobic landfill leachate was more chemically reactive and played a more important role in mobilizing heavy metal, especially mercury, at early landfill stabilization times. However, the S content of HA from the semi-aerobic landfill increased over time, suggesting that more S was stabilized in HA as the landfill stabilization time was extended. The analytical results for the FTIR and NMR showed that the HA from the anaerobic landfill contained more aromatic groups, while HA from the semi-aerobic landfill had more oxygen-containing groups. The aromatic components of the HA from both the anaerobic and semi-aerobic landfills increased over time, suggesting that the maturity and humification degree of HA increased during the stabilization process.
authors: State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China. xlchai@tongji.edu.cn
authors: Chai
authors: C
authors: Xiaoli
authors: Hao
authors: H
authors: Yongxia
authors: Liu
authors: L
authors: Guixiang
authors: Zhao
authors: Z
authors: Xin
authors: Zhao
authors: Z
authors: Youcai
mesh_terms: D000332:Aerobiosis; D002247:Carbon Isotopes; D004784:Environmental Monitoring; D006812:Humic Substances / Q000032:analysis*; D009682:Magnetic Resonance Spectroscopy; D012037:Refuse Disposal; D017550:Spectroscopy, Fourier Transform Infrared; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D002247:Carbon Isotopes; D006812:Humic Substances; D014874:Water Pollutants, Chemical