Parallel faction analysis combined with two-dimensional correlation spectroscopy reveal the characteristics of mercury-composting-derived dissolved organic matter interactions

• Published in: Journal of hazardous materials 2020-02, Vol.384, p.121395, Article 121395
• Main Authors: Cui, Hong-Yang, Zhang, Shu-Bo, Zhao, Mao-Yuan, Zhao, Yue, Wei, Zi-Min
• Format: Article
• Language: English
• Subjects: Dissolved organic matter (DOM); Mercury; Parallel factor analysis (PARAFAC); Two-dimensional correlation spectroscopy (2DCOS)
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2019.121395

[Display omitted] •PARAFAC combined 2DCOS & MSV equation can describe the binding of contaminant and DOM.•The Hg2+-binding PARAFAC component peaks were accurately evaluated.•Humic-like components showed high Hg2+-binding rate and Hg2+-binding capacity.•High humic-like containing composts can be amended to Hg contaminated soil. Dissolved organic matter (DOM) is regarded as the environmentally friendly substance. Strong complexes could be formed between DOM and heavy metals. Thus, the distribution, bioavailability, toxicity, and fate of heavy metals could be controlled in the environment. The widely spread method for characterizing metal-organic interactions is restricted to combine parallel faction analysis (PARAFAC) with the complexation model. However, a DOM PARAFAC component always contains two or more peaks. Therefore, the traditional method cannot reveal the inner changes of PARAFAC components or whether all the DOM peaks in one PARAFAC component are bound with metal during the metal-organic binding process. In this work, two-dimensional correlation spectroscopy (2DCOS) combined with PARAFAC and the complexation model were employed to reveal the binding speed and ability of different fluorescent peaks from DOM PARAFAC components during the binding process of mercury (Hg2+) to DOM. The results in this study showed that during the Hg2+-DOM binding process, fluorescent peaks in tryptophan-like component all presented Hg2+-binding ability. However, only humic-like component ligands showed Hg2+-binding ability. With these promising results, the true Hg2+ binding rate and ability of different DOM ligands can be revealed, which is helpful for addressing environmental pollution.