Utilization of pumice from Sungai Pasak, West Sumatera, Indonesia as low-cost adsorbent in removal of manganese from aqueous solution

Abstract

Adsorption of manganese (Mn) from aqueous solution by using pumice from Sungai Pasak, West Sumatera, Indonesia as low-cost adsorbent was studied. Batch experiments were carried out at ambient temperature (25°C) and 100 rpm of agitation speed to examine the effect of various experimental parameters on the removal of Mn such as solution pH, dose of adsorbent, particle size of adsorbent, initial concentration and contact time. The Langmuir and Freundlich models were employed to characterize the adsorption isotherm of Mn by the pumice. The results revealed that the optimum condition of Mn removal by pumice were 0.3 g/L of adsorbent dose, 90 min of contact time of adsorption, <149 µm of particle size, 4 of pH solution and 6 mg/l of Mn concentration with 171 mg Mn/g pumice of adsorption capacity. The Freundlich model was found to better fitting of adsorption isotherm within the concentration range studied. This study indicated that pumice from Sungai Pasak, West Sumatera, Indonesia has potential for Mn removal from groundwater or other polluted waters.