Department of Environmental Engineering, Faculty of Agriculture, Kochi University, B 200, Monobe, Nankoku, Kochi 783 8502, Japan
The present investigation attempted to develop the ceramic adsorbent media in order to remove the mercury from aqueous phase. Two ceramics, akadama volcanic ash soil-ceramic (Aceramic) and improved magnesium oxide impregnated akadama volcanic ash soil-ceramic (MAceramic) were produced from raw akadama volcanic ash soil by heating process to determine the Hg(II) adsorption capacity. Adsorption experiments of ceramics were performed as a function of contact time, solution pH, adsorbent dosage and adsorbate concentration following the batch mode operation. Results clearly revealed the adsorption capacity (265±8.5 μg/g) of MA-ceramic is significantly higher (~12 times) than that of the A-ceramic material. The adsorption was largely pH dependent and neutral pH was associated with higher mercury adsorption capacity in both ceramics. MA-ceramic showed 94% and 86% desorption and resorption capacities, respectively.