Journal
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
Volume 3, Issue 4, Pages 2982-2990Publisher
ELSEVIER SCI LTD
DOI: 10.1016/j.jece.2015.03.004
Keywords
Dissolved organic matter; Black carbon; XAD-8; DEAE-cellulose; C-13 NMR; FT-ICR MS
Categories
Funding
- US Geol. Survey Water Resources Research Institutes National Competitive grant
- Office of Vice President for Research, University of Minnesota
- University of Minnesota Retirees Association
Ask authors/readers for more resources
Chemical characteristics of dissolved organic matter (DOM) extracted from an ombrotrophic bog in northern Minnesota by two methods - XAD-8 and DEAE-cellulose - were compared using C-13 NMR spectroscopy, excitation-emission matrix fluorescence spectroscopy (EEMS), and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). DOM extracted with XAD-8, a relatively hydrophobic sorbent, had a larger C-13 NMR signal in the aromatic carbon region, but DOM extracted by DEAE-cellulose, a weak anion exchanger, had a larger signal in the carboxylic carbon region. DOM extracts prepared by the two methods were similar in their overall chemical characteristics that serve as proxies for organic matter sources. For example, only small differences were observed in the fluorescence index (FI) values of the extracts, and all values were within the range expected for terrestrially-derived DOM. EEMS spectra of both extracts had humic-like peak A areas smaller than that of standard reference Suwannee River fulvic acid. Of 2801 distinct chemical formulas assigned during FT-ICR MS analysis of the two extracts, 66% were present in both; 15% were unique to the XAD-8 extract, and 19% were unique to the DEAE-cellulose extract. Van Krevelen plots showed that the DEAE-cellulose extract had more tannin-like and condensed aromatic entities and formulas with higher O/Cratios, whereas the XAD-8 extract had more lignin-like material and formulas with higher H/C ratios. Overall, differences in chemical characteristics of the extracts reflect the mechanisms by which the extractants operate. (C) 2015 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available