The Fe (II) and Mn (II) adsorption in acid mine drainage using various granular sizes of activated carbon and temperatures

Abstract

Acid mine drainage (AMD) from coal mining activities contains Fe and Mn concentrations that often exceed environmental quality requirements. This study aims to determine the effect of the coal material size and temperature on the adsorption process of Fe and Mn metals contained in AMD using activated carbon made with a composition of 60% coal and 40% ZnCl2. For characterizing activated carbon, surface morphological was analyzed using SEM method, and surface area was analyzed using BET method. Meanwhile, for measuring Fe and Mn concentrations, the researchers used atomic absorption spectrophotometry. The adsorption process was carried out with various granular sizes of activated carbon (20, 28, 35, 48 and 60 mesh) and temperature (25, 35, 40, 45 and 50°C). The results showed that the maximum adsorption of Fe was 100% occurred in the treatment with an activated carbon size of 60 mesh and a temperature of 45°C, while the maximum adsorption of Mn was 11.91% in the treatment with an activated carbon size of 60 mesh and a temperature of 50°C. Furthermore, the activated carbon of coal is highly effective as an adsorbent for Fe in AMD waste but less effective for Mn.