Experimental study on removing Mn2+ from micro-polluted water by eggshell with static absorption

The effect on treatment of the Micro-polluted water whose concentration of Mn²⁺ is 2 mg/L are studied by means of static absorption under different conditions. The experimental results show that adsorbent dosage is 2.0 g, the optimum condition is pH =7.0, adsorption time is about 300 minutes, the adsorption rate of Mn²⁺ can be up to 95.66%. The concentration of Mn²⁺ can be reduced to 0.087 mg/L, which comes up to the standard of GB5749-85. In the meantime, the Adsorption isotherm, Langmuir adsorption isotherm and Freundlich adsorption isotherm are also explained in the paper. The result shows the Langmuir model can reflect the process of adsorption better than Freundlich model.