Conference paper

Interaction of Metal Ions with Hydrous Oxide Surfaces

Werner Stumm ; Institute of Aquatic Sciences (EAW AG) Swiss Federal Institute of Technology (ET.HJ. Zurich
Herbert Hohl ; Institute of Aquatic Sciences (EAW AG) Swiss Federal Institute of Technology (ET.HJ. Zurich
Felix Dalang ; Institute of Aquatic Sciences (EAW AG) Swiss Federal Institute of Technology (ET.HJ. Zurich

Abstract

In this paper, the results on the adsorption of cation on
hydrous Si02, Ah03 and 'Mn02 surfaces are presented. Robust
(kinetically inert) complexes, e. g. [Co(NH3) 6]3+, contrary to metal
ions, e. g. Pb · aq2+, are not able to displace the alkalimetric titration
curves of hydrous oxides. In the case of robust complexes the
pH-dependence of adsorption is only the function of the 1surface
charge (and its pH-dependence). The interpretation of metal ion
adsorption in terms of different models is also .given.
In solution of monomeric ·metal species, hydrolysis need not
be invoked to account for the pH-dependence of adsorpti,on to
hydrous oxide surfaces; this dependence can be explained with the
basicity of the Meo- gfoup and the affinity of this group to the
metal ion. Polymeric or colloidal metal species are usually adsorbed
strongly to surfaces; in this case the surface substrate, as
long as the surface charge is opposite to the charge of the adsorbing
species, has little influence upoP.. the adsoription.

Keywords

Hrčak ID:

196441

URI

https://hrcak.srce.hr/196441

Publication date:

22.12.1976.

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