Detail publikačního výsledku
Conformational behavior of lignite humic fractions separated by sequential pH-extractions
KUČERÍK, J., CONTE, P., PEKAŘ, M., PICCOLO, A.
Original Title
Conformational behavior of lignite humic fractions separated by sequential pH-extractions
English Title
Conformational behavior of lignite humic fractions separated by sequential pH-extractions
Type
Peer-reviewed article not indexed in WoS or Scopus
Original Abstract
A bulk humic acid (HA) extracted from a South Moravian lignite was further fractionated by sequential extraction in buffers at different pHs. All samples were analyzed by high performance size exclusion chromatography (HPSEC) and elemental analysis. Weight-averaged molecular weights (Mw) of fractions dissolved at pH 7, 8, and 9 were larger than for the parent bulk HA, thereby indicating that Mw of humic matter is related only to molecular size as affected by sample hydration rather than its molecular mass. Moreover, hydration radius was a function of the specific chemical properties of humic fractions. Addition of small amount of either mineral (HCl) or organic acid (formic, acetic, propionic) to humic solutions induced significant changes in conformational arrangements of the treated sample in respect to control. Also the conformational changes among humic fractions depended on their different molecular composition and suggested a weakly-bound supramolecular association of different humic molecules in solution.
English abstract
A bulk humic acid (HA) extracted from a South Moravian lignite was further fractionated by sequential extraction in buffers at different pHs. All samples were analyzed by high performance size exclusion chromatography (HPSEC) and elemental analysis. Weight-averaged molecular weights (Mw) of fractions dissolved at pH 7, 8, and 9 were larger than for the parent bulk HA, thereby indicating that Mw of humic matter is related only to molecular size as affected by sample hydration rather than its molecular mass. Moreover, hydration radius was a function of the specific chemical properties of humic fractions. Addition of small amount of either mineral (HCl) or organic acid (formic, acetic, propionic) to humic solutions induced significant changes in conformational arrangements of the treated sample in respect to control. Also the conformational changes among humic fractions depended on their different molecular composition and suggested a weakly-bound supramolecular association of different humic molecules in solution.
Keywords
humic substances, lignite, HPSEC
Key words in English
humic substances, lignite, HPSEC
Authors
KUČERÍK, J., CONTE, P., PEKAŘ, M., PICCOLO, A.
Released
01.01.2003
ISBN
1018-4619
Periodical
Fresenius Environmental Bulletin
Volume
12
Number
7
State
Federal Republic of Germany
Pages from
683
Pages count
7
Full text in the Digital Library
BibTex
@article{BUT41503,
author="Jiří {Kučerík} and Pelegrino {Conte} and Miloslav {Pekař} and Alessandro {Piccolo}",
title="Conformational behavior of lignite humic fractions separated by sequential pH-extractions",
journal="Fresenius Environmental Bulletin",
year="2003",
volume="12",
number="7",
pages="7",
issn="1018-4619"
}