Conductometric study of the dissociation behavior of humic and fulvic acids
Identifikátory výsledku
Kód výsledku v IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26310%2F18%3APU127761" target="_blank" >RIV/00216305:26310/18:PU127761 - isvavai.cz</a>
Výsledek na webu
<a href="http://dx.doi.org/10.1016/j.reactfunctpolym.2018.04.017" target="_blank" >http://dx.doi.org/10.1016/j.reactfunctpolym.2018.04.017</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1016/j.reactfunctpolym.2018.04.017" target="_blank" >10.1016/j.reactfunctpolym.2018.04.017</a>
Alternativní jazyky
Jazyk výsledku
angličtina
Název v původním jazyce
Conductometric study of the dissociation behavior of humic and fulvic acids
Popis výsledku v původním jazyce
The dissociation behavior of humic and fulvic acids was characterized on the basis of conductometric measurements. It was confirmed that dissociation is strongly affected by the content of humic or fulvic acids in aqueous solution. In the case of fulvic acids, the dilution effect connected with the increase of dissociation degree and the values of activity coefficients was the main factor influencing their dissociation ability. In the case of humic acids, their aqueous leachates were used and characterized as the main fractions functioning actively in natural systems. These fractions can be rich in acidic functional groups and the chemical compositions of these fractions change with their contents in the leachates. The amount of the dissolved humic fraction, its chemical character and its dissociation ability can be considered to result from equilibrium between dissolved and undissolved humic substances. A maximum was observed for the dependence of the dissociation degree on the concentration of humic leachates. In less concentrated leachates, less soluble humic particles with weaker functional groups were able to be dissolved. The increase of humic contents in leachates caused smaller amounts of soluble fractions with the weakest functional groups to remain in an undissolved form, which led to an increase in the degree of dissociation up to a maximum. In the case of fulvic acids, the dissociation degree increases with decreasing concentration as a result of the dilution. Two different values of pKa were determined for each humic and fulvic sample. The first was determined for higher concentrations, where pKa values are practically constant. The second was the value extrapolated to infinite dilution.
Název v anglickém jazyce
Conductometric study of the dissociation behavior of humic and fulvic acids
Popis výsledku anglicky
The dissociation behavior of humic and fulvic acids was characterized on the basis of conductometric measurements. It was confirmed that dissociation is strongly affected by the content of humic or fulvic acids in aqueous solution. In the case of fulvic acids, the dilution effect connected with the increase of dissociation degree and the values of activity coefficients was the main factor influencing their dissociation ability. In the case of humic acids, their aqueous leachates were used and characterized as the main fractions functioning actively in natural systems. These fractions can be rich in acidic functional groups and the chemical compositions of these fractions change with their contents in the leachates. The amount of the dissolved humic fraction, its chemical character and its dissociation ability can be considered to result from equilibrium between dissolved and undissolved humic substances. A maximum was observed for the dependence of the dissociation degree on the concentration of humic leachates. In less concentrated leachates, less soluble humic particles with weaker functional groups were able to be dissolved. The increase of humic contents in leachates caused smaller amounts of soluble fractions with the weakest functional groups to remain in an undissolved form, which led to an increase in the degree of dissociation up to a maximum. In the case of fulvic acids, the dissociation degree increases with decreasing concentration as a result of the dilution. Two different values of pKa were determined for each humic and fulvic sample. The first was determined for higher concentrations, where pKa values are practically constant. The second was the value extrapolated to infinite dilution.
Klasifikace
Druh
J<sub>imp</sub> - Článek v periodiku v databázi Web of Science
CEP obor
—
OECD FORD obor
10403 - Physical chemistry
Návaznosti výsledku
Projekt
<a href="/cs/project/LO1211" target="_blank" >LO1211: Centrum materiálového výzkumu na FCH VUT v Brně - udržitelnost a rozvoj</a><br>
Návaznosti
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Ostatní
Rok uplatnění
2018
Kód důvěrnosti údajů
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Údaje specifické pro druh výsledku
Název periodika
REACTIVE & FUNCTIONAL POLYMERS
ISSN
1381-5148
e-ISSN
1873-166X
Svazek periodika
128
Číslo periodika v rámci svazku
1
Stát vydavatele periodika
NL - Nizozemsko
Počet stran výsledku
5
Strana od-do
24-28
Kód UT WoS článku
000435061900003
EID výsledku v databázi Scopus
2-s2.0-85046654765