Synthesis of AgCl nanoparticles-loaded hydrotalcite as highly efficient adsorbent for removal of thiocyanate

AgCl nanoparticles supported on layered double hydrotalcite (AgCl/LDH) were synthesized and used as adsorbent to remove thiocyanate from aqueous solution. The as-prepared AgCl/LDH was characterized with scanning electron microscopy (SEM), transmission electron microscope (TEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The results indicated that AgCl nanoparticles were loaded on LDH, due to the reaction of Cl−-containing LDH with Ag+ during the synthesis process. The loading of AgCl nanoparticles on LDH remarkably improved the adsorptive removal efficiency of thiocyanate. The influencing factors such as initial solution pH, temperature, adsorbent dosage and Ag content were systematically investigated. The adsorption isotherm of thiocyanate on AgCl/LDH followed the Langmuir isotherm model and the saturated adsorption capacity of AgCl/LDH for thiocyanate was 108.6 mg g−1. The mechanism for the promotion of AgCl/LDH to the adsorptive removal of thiocyanate was analyzed.