ГЛАСНИК ХЕМИЈСКОГ ДРУШТВА БЕОГРАД

摘要: The adsorption of hydrogen and hydroxide ions at the natural magnetite aqueous electrolyte interface was studied by the potentiometric titration method. The adsorption density (TH-гон) was calculated from the experimental data, and presented as function of the solution pH and of the electrolyte (NaCl) concentration. From the experimental data obtained, it was concluded that the magnetite shows anomalous behaviour with respect to H+ adsorption on other oxides. The observed shift in the zero point of charge (zpc) of the natural magnetite to higher pH values is explained in terms of the soluble polymeric hydro-complexes of iron present in the system investigated. Accordingly, the experimental zpc of the natural magnetite occurs at the pH value which corresponds to the isolectric point of the soluble complexes of iron.