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Updated: Jul 20, 2026

Quantification of Heavy Metals and Other Inorganic Contaminants on the Productivity of Microalgae
Published on: July 10, 2015
The origin of aluminum flocs in polluted streams
Gerhard Furrer1, Brian L Phillips, Kai-Uwe Ulrich
1Institute of Terrestrial Ecology, Eidgenössische Technische Hochschule Zürich, Grabenstrasse 3, CH-8952 Schlieren, Switzerland. furrer@ito.umnw.ethz.ch
Abstract:
About 240,000 square kilometers of Earth's surface is disrupted by mining, which creates watersheds that are polluted by acidity, aluminum, and heavy metals. Mixing of acidic effluent from old mines and acidic soils into waters with a higher pH causes precipitation of amorphous aluminum oxyhydroxide flocs that move in streams as suspended solids and transport adsorbed contaminants. On the basis of samples from nine streams, we show that these flocs probably form from aggregation of the epsilon -Keggin polyoxocation AlO4Al12(OH)24(H2O)12(7+)(aq) (Al13), because all of the flocs contain distinct Al(O)4 centers similar to that of the Al13 nanocluster.
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