Fig. 5. (a) Desferrioxamine B (DFOB); (b) the ferric complex of DFOB (FOB). Calculated charge (bold lines represent the sum of all species bearing the same type of charge: positive, negative or neutral) compared to measured values of adsorption of DFOB and FOB to Ca-montmorillonite and Ca-kaolinite (dotted lines) vs. pH. Experimental conditions: 1.0 mM DFOB or FOB; 5 g L^–1 clay minerals; pH values 4.0, 6.0, 7.5, 9.0; I = 0.01 M (KClO₄); two replicates.