Utilization of UV–Vis and synchronous fluorescence heterospectral two-dimensional correlation analysis on the structural variation of landfill leachate during membrane bioreactor-reverse osmosis process

Abstract

Landfill leachate, a complex organic effluent generated during the sanitary landfilling process, poses a significant environmental threat if not properly managed. This study utilized fluorescence and UV–Vis spectroscopy in conjunction with two-dimensional correlation spectroscopy (2DCOS) to investigate the removal and transformation properties of landfill leachate during membrane bioreactor (MBR) and reverse osmosis (RO) processes. The results revealed that the MBR process effectively reduced the concentrations of chemical oxygen demand and total organic carbon, but had limited impact on complex structures and bio-refractory organic matter. Conversely, the RO process demonstrated effective trapping of organic pollutants, including both fluorescent and non-fluorescent components. Furthermore, 2DCOS analysis identified the sequence of changes in landfill leachate substances: unsaturated aldehydes and ketones > fulvic-like component/protein-like component > aromatic compounds. These findings offer valuable insights for the development of economical and efficient landfill leachate treatment procedures.