Binding characteristics of copper onto biochar-derived DOM using general, heterospectral and moving-window two-dimensional correlation analyses

Jun Wu; Wenxin Tu; Chunping Li; Feng He

doi:10.1016/j.jhazmat.2022.129021

Binding characteristics of copper onto biochar-derived DOM using general, heterospectral and moving-window two-dimensional correlation analyses

J Hazard Mater. 2022 Aug 5:435:129021. doi: 10.1016/j.jhazmat.2022.129021. Epub 2022 Apr 27.

Authors

Jun Wu¹, Wenxin Tu², Chunping Li³, Feng He⁴

Affiliations

¹ Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, China; Center for Membrane and Water Science & Technology, Zhejiang University of Technology, Hangzhou, China; Zhejiang University of Technology Engineering Design Group Co., Ltd, Hangzhou, China.
² Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, China; Zhejiang University of Technology Engineering Design Group Co., Ltd, Hangzhou, China.
³ Zhejiang University of Technology Engineering Design Group Co., Ltd, Hangzhou, China.
⁴ Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, China. Electronic address: fenghe@zjut.edu.cn.

PMID: 35490630
DOI: 10.1016/j.jhazmat.2022.129021

Abstract

Dissolved organic matter released from biochar (biochar-derived DOM, BDOM) could dominate the environmental behavior and fate of trace metals by forming BDOM-metal complexes. Here general, heterospectral as well as moving-window (MW) two-dimensional correlation spectroscopy (2DCOS) analyses of synchronous fluorescence and Fourier transform infrared spectra were employed to explore the heterogeneous binding characteristics between sludge BDOM and Cu(II). The results revealed that Cu-BDOM binding first occurred in the fulvic-like (368-380 nm), then humic-like (428 nm) fluorescent fractions, followed by infrared groups of phenolic hydroxyl groups, carboxylate, COH of polysaccharide groups, CC of aromatic carbon, CH of aliphatics and COC of aliphatic ethers. The binding affinity of the hydrophilic groups was stronger than that of hydrophobic groups in BDOM towards Cu(II). Fluorescence components in BDOM played a decisive role in the binding of Cu(II) with trace concentration (1 μM), while infrared functional groups made a substantial contribution in the complexation of Cu(II) with higher concentration (10-100 μM). The concentration of final configuration transformation point (11.7 μmol/mg in this study) by MW2DCOS analysis was suggested as an actual binding threshold that was helpful for evaluating their environmental behaviors.

Keywords: Binding affinity; Biochar; Copper; Dissolved organic matter; Two-dimensional correlation spectroscopy.

MeSH terms

Charcoal / chemistry
Copper* / chemistry
Humic Substances* / analysis
Spectrometry, Fluorescence

Substances

Humic Substances
biochar
Charcoal
Copper