TY - JOUR
T1 - Characterization of humic acids in sediments from dam reservoirs by pyrolysis-gas chromatography/mass spectrometry using tetramethylammonium hydroxide
T2 - Influence of the structural features of humic acids on iron(II) binding capacity
AU - Fukushima, Masami
AU - Furubayashi, Ken
AU - Fujisawa, Naotaka
AU - Takeuchi, Mio
AU - Komai, Takeshi
AU - Otsuka, Keishi
AU - Yamamoto, Mitsuo
AU - Kawabe, Yasunari
AU - Horiya, Shigekazu
N1 - Funding Information:
The authors are grateful for the financial support from the New Energy and Industrial Technology Development Organization (NEDO).
PY - 2011/7
Y1 - 2011/7
N2 - The structural features of humic acids (HAs) isolated from sediments on the bottom of dam reservoirs that can affect their binding capacities for Fe(II) were investigated by pyrolysis-gas chromatography/mass spectroscopy using tetramethylammonium hydroxide (TMAH-py-GC/MS). The binding capacities for Fe(II) increased with increasing O/C molar ratio, suggesting that the oxygen-containing functional group content plays a role in the binding of Fe(II). However, it was not possible to identify specific binding-sites for Fe(II) by TMAH-py-GC/MS analysis. Although C16:1ω7, iso-C 15:0 and anteiso-C17:0 fatty acids, which serve as molecular markers of anaerobic microbial activity, were detected in all of the HA samples, the contents of these acids were not correlated with binding capacities for Fe(II). However, the ratio of C16:0 to C 16:1ω7 fatty acids, which is used as an index of anaerobic bacterial activity, increased with increasing Fe(II) binding capacities of the HAs. It thus appears likely that the activities of anaerobic bacteria on the bottom of dam reservoirs contribute to alterations in the structural features for HAs, and that this process results in increased binding capacities for Fe(II).
AB - The structural features of humic acids (HAs) isolated from sediments on the bottom of dam reservoirs that can affect their binding capacities for Fe(II) were investigated by pyrolysis-gas chromatography/mass spectroscopy using tetramethylammonium hydroxide (TMAH-py-GC/MS). The binding capacities for Fe(II) increased with increasing O/C molar ratio, suggesting that the oxygen-containing functional group content plays a role in the binding of Fe(II). However, it was not possible to identify specific binding-sites for Fe(II) by TMAH-py-GC/MS analysis. Although C16:1ω7, iso-C 15:0 and anteiso-C17:0 fatty acids, which serve as molecular markers of anaerobic microbial activity, were detected in all of the HA samples, the contents of these acids were not correlated with binding capacities for Fe(II). However, the ratio of C16:0 to C 16:1ω7 fatty acids, which is used as an index of anaerobic bacterial activity, increased with increasing Fe(II) binding capacities of the HAs. It thus appears likely that the activities of anaerobic bacteria on the bottom of dam reservoirs contribute to alterations in the structural features for HAs, and that this process results in increased binding capacities for Fe(II).
KW - Fatty acids
KW - Fe(II) binding capacity
KW - Humic acid
KW - Sediment
KW - TMAH-pyrolysis-GC/MS
UR - http://www.scopus.com/inward/record.url?scp=79955911217&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=79955911217&partnerID=8YFLogxK
U2 - 10.1016/j.jaap.2011.03.008
DO - 10.1016/j.jaap.2011.03.008
M3 - Article
AN - SCOPUS:79955911217
VL - 91
SP - 323
EP - 331
JO - Journal of Analytical and Applied Pyrolysis
JF - Journal of Analytical and Applied Pyrolysis
SN - 0165-2370
IS - 2
ER -