Kinetics and Thermodynamics Studies of Cobalt (II)Adsorption onto Alumina

Adsorption for alumina-cobalt (II) ions solution system was investigated as a function ofadsorbent dose,contact time, temperature, pH of solution and initial concentration of adsorbate.The optimum conditions for removal of cobalt (II) ions were found as pH 7.5-8.5, adsorbent doseof solution 20 gl-1,equilibrium time 90 minutes and initial concentration range 5-50mgl-1.Pseudo-second-order kinetics was observed for adsorption of cobalt while cobalt removal processdoes not seem to control the intra-particle diffusion. Langmuir, Freundlich and Dubnin-Radushkevich isotherm models were applied to analyze the equilibrium isotherms for adsorptionof cobalt (II) ions onto alumina. The experimental results indicated that equilibrium data followsthe Langmuir model within used concentration range.