مرکز منطقه ای اطلاع رساني علوم و فناوري - Removal of Cadmium Ions from Aqueous Solutions by Using Manganese Oxide Coated Sepiolite

Abstract :

In this study, the usability of manganese oxide coated sepiolite as an adsorbent for the removal ofcadmium ions from aqueous solutions was investigated. For this purpose, the effects of adsorbentdosage, pH, initial solution concentration and temperature on the adsorption process wereinvestigated. Experimental results indicated that the cadmium removal yield increased with increasing adsorbent dosage, pH and temperature. Adsorption capacity increased while the removal yield was decreased with increasing initial concentration.The fitting of the adsorption equilibrium data to Langmuir and Freundlich isotherm models was investigated. It was observed that the cadmium removal process using manganese oxide coated sepiolite was obeyed the Langmuir isotherm model. Maximum adsorption capacities were found as 78.74 mg/g for 25°C, 99.01 mg/g for 35°C and 109.89 mg/g for 45°C. The thermodynamic investigations indicated that the adsorption process was endothermic and spontaneous in nature and the randomness increased. Consequently, manganese oxide coated sepiolite can be used to remove cadmium ions from aqueous solutions as a cheap and effective adsorbent.