Adsorption of Humic Substances on Goethite:  Comparison between Humic Acids and Fulvic Acids

• Published in: Environmental science & technology Vol. 40; no. 24; pp. 7494 - 7500
• Main Authors: Weng, Van Riemsdijk, Willem H, Koopal, Luuk K, Hiemstra, Tjisse
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 15.12.2006
• Subjects: Acids; Adsorption; aluminum-oxide; Benzopyrans - chemistry; clay-minerals; Comparative analysis; fractionation; fulvic acids; Humic acids; Humic Substances; Hydrogen-Ion Concentration; ion-binding; Ions; Iron Compounds - chemistry; isotherms; Measurement; Minerals; Models, Chemical; natural organic-matter; nica-donnan model; Particulates; Protons; Q1; stoichiometry; surfaces; water interface

The adsorption of humic acids (HA) to goethite (at pH 3−11) and the proton co-adsorption (at pH 4.0, 5.5, and 7.0) were measured, and the results were compared to those of fulvic acids (FA). Compared to FA, the adsorption of HA is stronger and more ionic strength dependent. The adsorption of both HA...