High-efficiency removal of low-concentration Hg(II) from aqueous solution by bentonite nanocomposite: Batch and fixed-bed column adsorption study

A nanocomposite based on bentonite was synthesized. Its adsorption properties for Hg(II) were evaluated by batch and fixed-bed column adsorption experiments. The results showed that the nanocomposite was an efficient adsorbent for the treatment of wastewater containing low-concentration Hg(II). It removed more than 92% of Hg(II) from aqueous solution with a pH ranged from 4.00 to 12.00. Its adsorption capacity for Hg(II) increased linearly with the increase of mercury concentration. The nanocomposite had excellent reusability. HCl solution can be used to elute Hg(II) ions loaded. The developed Bohart-Adams model can be used for the design of adsorption column.