Nitrate Adsorption capacity of Activated Gamalama Volcanic Ash

Abstract

<p>The adsorption process of nitrate from an aqueous solution by using activated Gamalama volcanic ash was investigated. Gamalama volcanic ash (VA) was activated with HNO3 2M. The effect of adsorbent mass and initial nitrate concentration on nitrate adsorption were observed in this study. The adsorption process was conducted using a various mass of adsorbent (1 g, 2 g, 4 g, 6 g, and 8 g), various initial concentrations of nitrate (20 mg/L, 30 mg/L,40 mg/L, 50 mg/L, and 60 mg/L). The increasing of adsorbent mass decreased the adsorption capacity was observed. It was also found that the increase in initial concentration increased the adsorption capacity. The highest nitrate adsorption capacity showed by 1 gram adsorbent for 0.167 mg/g, and at nitrate initial concentration 80 mg/L, for 1.831 mg/g. Adsorption isotherm of nitrate on activated VA was determined and figured. These isotherms were modelled according to Freundlich and Langmuir adsorption isotherm.</p>