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The geochemical behavior of aluminum in acidified surface waters

D. Kirk Nordstrom·J.W. Ball
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Abstract

Speciation calculations for aluminum, in water samples taken from a drainage basin containing acid mine waters, demonstrate a distinct transition from conservative behavior for p H. below 4.6 to nonconservative behavior for p H. above 4.9. This transition corresponds to the pK for the first hydrolysis constant of the aqueous aluminum ion and appears to be a consistent phenomenon independent of field location, ionic strength, and sulfate concentration. Nonconservative behavior is closely correlated with the equilibrium solubility of a microcrystalline gibbsite or amorphous aluminum hydroxide.

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D. Kirk Nordstrom, J.W. Ball. 1986. The geochemical behavior of aluminum in acidified surface waters. https://doi.org/10.1126/science.232.4746.54

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