Describing the adsorption of phosphate, citrate and selenite on a variable-charge mineral surface

摘要: The effects were measured of varying the pH and concentration adsorbing ion on adsorption phosphate, citrate selenite by goethite charge conveyed to surface. ability model Bowden et al. describe these was investigated. observed closely described model, provided it modified permit adsorbed ions reside in a plane between surface diffuse layer. requires that individual ionic species be considered. For phosphate selenite, divalent appeared only whereas for trivalent ion. also depends electrostatic potential adsorption. This decreases with increasing pH. Thus explained changes this potential, together proportion present. Because made more negative, decreased further difficult, as result, at constant did not follow Langmuir equation. showed increase negative result partly balanced an uptake protons most marked near-neutral net per least.