Synthesis, characterization, and caesium adsorbent application of trigonal zinc hexacyanoferrate (II) nanoparticles

Trigonal zinc hexacyanoferrate (TZHF) nanoparticle adsorbents for effective caesium ion (Cs+) removal were prepared using the chemical coprecipitation method. The morphologies of zinc hexacyanoferrate (ZHF) were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HR-TEM), and energy-dispersive X-ray spectroscopy (EDS). These analyses confirmed that the trigonal structure of ZHF and surface area is 43.08 m2/g. Cs+ removal was dependent on pH, with the greatest adsorption occurring under near-neutral conditions, and the removal process decreased with increasing pH. The Langmuir model was determined to be suitable for describing the adsorption process of Cs+ by ZHF. The mechanism of Cs+ adsorption was examined by Total Reflection X-ray Fluorescence (TXRF) using the gallium internal standard. In addition, the main mechanism of Cs+ adsorption by the ion exchange process was proposed and discussed.