The adsorption of colloidal trivalent iron on neutral, acid and basic Al2O3 from aqueous solution as a function of pH has been studied. The dependence of sorption of pH is characterized by a maximum,
whose position depends on the nature of colloidal particles and surface properties of the sorbents. Adsorption isotherms for
the given range of sorbent loading can be expressed by the Langmuir adsorption equation.