The p.z.c. and i.e.p. of γ-Al2O3 and TiO2

Specific influence of univalent cations on the ionization of alumina-coated TiO2 particles and on the adsorption of poly(acrylic)acid

“…Numerous studies have reported specific surface adsorption of Li + on mineral substrates such as γ -alumina, α-alumina, titania, and hematite [33][34][35][36][37]. This specific adsorption is also observed in Fig.…”

“…Because of its high heat of immersion, alumina strongly promotes water structure in its vicinity (see Ref. [35] and references therein). The monovalent binding sequence Li + > Na + > TMA + = Cl − found here with the counterion titration method is therefore in good agreement with the structure-making/structure-breaking model.…”

Comparison between batch and column experiments to determine the surface charge properties of rutile TiO2 powder

“…This could be assigned to a sodium specific adsorption. Indeed, according to Tschapek et al [27], the IEP must shift toward higher pH in the case of specific adsorption of cations. At high ionic strength (0.1 M), Raman and XPS spectra have revealed sorption of perchlorate anions, but Raman spectroscopy in the alkaline range of pH also detected the sorption of contact ion pairs Na + ClO − 4 .…”

Zeta Potentials and Yield Stresses of Silica Suspensions in Concentrated Monovalent Electrolytes: Isoelectric Point Shift and Additional Attraction

“…Electrophoretic mobility measurements generally indicate that the magnitude of the negative zeta potential at high pH increases as the Hofmeister series (Cs + < K + < Na + < Li + ) (5,13,14) with Cs + producing lower magnitude negative zeta potentials than Li + . On the other hand, the inverse Hofmeister series is observed for both ion adsorption (18,19) and zeta potential measurements (20,21) for materials such as alumina, hematite, and zirconia, which have high isoelectric points.…”