Adsorption test using ultra-fine materials on heavy metals removal

Acid mine drainage (AMD) contains numerous heavy metals, which need appropriate treatment before releasing to the environment. This study reports Fe and Mn removal from AMD by adsorption using ultra-fine biochar derived from coal, peat, and coconut shell. Clamshell waste was used and compared with pure CaO as a conventional precipitant. All adsorption materials were tested in an artificial solution at different pH conditions and contact time at room temperature. The adsorption process reached equilibrium at 100 min. Neutral pH was the best condition to achieve a higher removal efficiency. Results showed that biochar could successfully remove >90 % Fe and 80 % Mn. The isotherm model of each sorption fit with the Langmuir model. Metals can be precipitated in 10 min using clamshell waste, which is comparable with pure CaO. biochar, pure CaO, and clamshell are potential materials to solve heavy metal pollution and increase pH in wastewater.