Étude des propriétés superficielles de quelques oxydes métalliques par chromatographie gazeuse inverse et par zétamétrie en milieux aqueux et organique

Inverse gas chromatography and zeta potential techniques are usedito study some of the surface properties of zinc oxide ZnO, monogai (essentially constituted; by ZnO), zinc hydroxide Zn (OH)2 and magnesium oxide MgO. The dispersive component of their surface energy,; their (Lewis) acide-base characteristics and isoelectic point (IEP) in both aqueous and organic-media, are determined in order to understand and predict the adhesive capacity of such oxides. We showed that the dispersive component of the surface energy γSD of these oxides depends; on temperature T ; irregularly for monogai and linearly for ZnO and Zn (OH)2- For MgO) γSD remains constant as a function of the temperature. It is shown, that Zn (OH)O exhibits the highest surface acidity followed respectively in decreasing acidity order by monogai, ZnO and MgO. Zeta potential measurements of the oxides in aqueous medium lead to the conclusion that MgO is more basic (IEP = 11) than the other oxides, whereas monogai is the most acidic one, in tema of Brönsted acide-base concept