Effective removal of aqueous silver by a layered copper thioantimonate

Abstract Efficient and effective removal of aqueous silver, especially at very low concentration, remains a great challenge. Herein, we report the synthesis, crystal structure and silver uptake performance of a layered copper thioantimonate [enH2]0.5Cu2SbS3·H2O (en = ethylenediamine, CuSbS-1). The typical silver uptake experiment of CuSbS-1 was performed by a batch equilibration technique at ambient temperature under different initial Ag+ concentration in the range of 0.04–50 mg/L for 12 h. CuSbS-1 exhibited excellent affinity for Ag+ ion with a high distribution coefficient Kd of 5.37 × 106 mL/g and high removal efficiency of close to 100%. The superior Ag+ ion adsorption was also impressive despite the acidic condition. Particularly, the Ag-loaded product can be eluted by KCl solution, and the recycled adsorbent can be further used for silver capture. The advantages make it a promising candidate for the remediation of Ag+-contaminated water source.