In situ study of the specific adsorption of HSO4-/SO42- ions on hematite by radiotracer technique

The specific adsorption of radiolabeled sulfate ions from perchlorate suppo rting electrolyte on hematite powder has been investigated. It was demonstr ated that a measurable adsorption occurs only at pH values under 5, The ads orption capacity of a given amount of hematite powder tends to a limiting v alue with decreasing pH. A Langmuir-like adsorption isotherm describes the concentration dependence of the adsorption of sulfate species, It was found that the experimental results are in good agreement with the model suggest ed recently (Hug, S. J. J. Colloid Interface Sci. 188, 415 (1997)). (C) 200 0 Academic Press.