Skip to Main content Skip to Navigation
Journal articles

Using Spectrophotometric Titrations To Characterize Humic Acid Reactivity at Environmental Concentrations

Abstract : Potentiometric titration is a common method to characterize dissolved organic matter (DOM) reactivity. Because of the sensitivity of pH electrodes, it is necessary to work with very high DOM (>1 g/L) concentrations that are unrealistic compared to those found in natural waters (0.1 to 100 mg/L). To obtain proton binding data for concentrations closer to environmental values, spectroscopic titration methodology is a viable alternative to traditional potentiometric titrations. Spectrophotometric titrations and UV−visible spectra of a diluted solution of purified Aldrich humic acid (5 mgDOC/L) are used to estimate changes in proton binding moieties as function of pH and ionic strength after calculation of differential absorbance spectra variations. After electrostatic correction of spectrophotometric data, there is a linear operational correlation between spectrophotometric and potentiometric data which can be used as a transfer function between the two properties. Spectrophotometric titrations are then used to determine the changes of humic acid protonation after adsorption onto α-alumina.
Document type :
Journal articles
Complete list of metadatas

https://hal-cea.archives-ouvertes.fr/cea-00512354
Contributor : Pascal Reiller <>
Submitted on : Monday, August 30, 2010 - 10:35:43 AM
Last modification on : Friday, October 2, 2020 - 6:30:31 PM

Identifiers

Collections

Citation

Noémie Janot, Pascal E. Reiller, G.V. Korshin, Marc Benedetti. Using Spectrophotometric Titrations To Characterize Humic Acid Reactivity at Environmental Concentrations. Environmental Science and Technology, American Chemical Society, 2010, 44 (17), pp.6782-6788. ⟨10.1021/es1012142⟩. ⟨cea-00512354⟩

Share

Metrics

Record views

364