Electroacoustic and Potentiometric Studies of the Hematite/Water Interface

Prediction of surface charge on oxides in salt solutions: Revisions for 1:1 (M+L−) electrolytes

“…Data from Penners et al (1986) for hematite in KCl (pH PZSE Ϫ IEP 0.2; logK L Ϫ Ϫ logK M ϩ ϭ Ϫ0.6) and Rosenqvist et al (2002) for gibbsite in NaCl (pH PZSE Ϫ IEP ϭ 1.0; logK L Ϫ Ϫ logK M ϩ ϭ Ϫ0.6) were the only data where both measurements were reported but the result was not consistent with the other data and the theoretical line shown in Figure 11. Reports of no difference between pH PZSE and IEP (Sprycha et al, 1989;Rietra et al, 2000;Gunnarsson et al, 2000Gunnarsson et al, , 2001Boily et al, 2001) were also not included in Figure 11 for the sake of clarity. It should be emphasized that substantial uncertainties exist in the experimental and predicted values shown in the figure.…”

Corrected Debye–Hückel analysis of surface complexation

“…For a 1:1 electrolyte this corresponds to a potential of approximately 25 mV and that value is independent of background salt concentration. Since zeta potentials on iron (hydr)oxide particles often are at least a factor of 2 higher [36,39], the slip plane must be located closer to the surface. The analysis of the relationship between slip planes and ion condensation in our present terminology in more detail could also be an issue for future studies.…”

Surface-Induced Electrolytic Dissociation of Weak Acids in Ethanol

“…Hematite was synthesized according to a modified recipe of Matijevic and Scheiner . A solution 0.02 M in FeCl 3 and 0.001 M in HCl was aged for 1 d at 100 °C in a sealed glass bottle.…”

“…Hematite was synthesized according to a modified recipe of Matijevic and Scheiner. 23 A solution 0.02 M in FeCl 3 and 0.001 M in HCl was aged for 1 d at 100 °C in a sealed glass bottle. Then the dispersion was cooled to room temperature, and the excess of acid was removed by a series of centrifugation-redispersion cycles, in which the supernatant was replaced with Milli-Q water until a concentrated dispersion reached pH 4.…”