The current study focuses on the characterization and comparative sorption of Cd2+ ions on silica, iron hydroxide and their equimolar mixed oxide (0.5 M SiO2:0.5 M Fe(OH)(3)) from aqueous solutions. These adsorbents are characterized for surface area, EDX, FTIR, TG/DTA, XRD and pH(PZC). Cd2+ sorption studies are performed at pH 5 in the temperature range 288-318 K. Sorption data are found well fitted to the Langmuir model with R-2 > 0.98. The mixed oxide has been found to have the highest selectivity towards the Cd2+ ions. Thermodynamic parameters show the process to be endothermic and spontaneous and also reveal that the electrostatic interactions play the dominant role in the overall mechanism of the uptake of Cd2+ ions. The Delta H degrees, Delta S degrees, and Delta G degrees values found for equimolar mixed oxide are the arithmetic mean of silica and iron hydroxide. (C) 2010 Elsevier B.V. All rights reserved.