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

摘要

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 mgg~(-1). The mechanism for the promotion of AgCl/LDH to the adsorptive removal of thiocyanate was analyzed.