Efficient removal of Hg in aqueous solution with fishbone charcoal as adsorbent.

The Hg removal performance of fishbone charcoal prepared from discarded fishbone has been investigated in this work. The XRD, FTIR, and BET results demonstrated that the main composition of fishbone charcoal was hydroxyapatite and the specific surface area was 117 m/g. The adsorption experiments indicated that fishbone charcoal had an extremely high adsorption capacity for Hg (243.77 mg/g). The excellent Hg adsorption capacity might be ascribed to the ion exchange of Hg to the Ca in the structure of fishbone charcoal, complexation of Hg with ≡Ca(OH) on the surface of fishbone charcoal, as well as electrostatic interaction between electronegative fishbone charcoal surface and cation Hg. This work transformed kitchen garbage (i.e., fishbone) into an effective mercury adsorbent with considerable capacity, giving a perspective sight for the utilization of solid waste.