| Summary: | Here, using Fe<sub>3</sub>O<sub>4</sub>@SiO<sub>2</sub> as a precursor, a novel core-shell structure magnetic Cu<sup>2+</sup> adsorbent (Fe<sub>3</sub>O<sub>4</sub>@zeolite NaA) was successfully prepared. Several methods, namely X-ray diffraction (XRD), Fourier transform infrared spectrometer (FTIR), Transmission electron microscope (TEM), Brunauer Emmett Teller (BET) and vibrating sample magnetometry (VSM) were used to characterize the adsorbent. A batch experiment was conducted to study the Cu<sup>2+</sup> adsorption capacity of Fe<sub>3</sub>O<sub>4</sub>@zeolite NaA at different pH values, contact time, initial Cu<sup>2+</sup> concentration and adsorbent does. It is found that the saturated adsorption capacity of Fe<sub>3</sub>O<sub>4</sub>@zeolite NaA on Cu<sup>2+</sup> is 86.54 mg/g. The adsorption isotherm analysis shows that the adsorption process of Fe<sub>3</sub>O<sub>4</sub>@zeolite NaA to Cu<sup>2+</sup> is more consistent with the Langmuir model, suggesting that it is a monolayer adsorption. Adsorption kinetics study found that the adsorption process of Fe<sub>3</sub>O<sub>4</sub>@zeolite NaA to Cu<sup>2+</sup> follows the pseudo-second kinetics model, which means that the combination of Fe<sub>3</sub>O<sub>4</sub>@zeolite NaA and Cu<sup>2+</sup> is the chemical chelating reaction. Thermodynamic analysis shows that the adsorption process of Fe<sub>3</sub>O<sub>4</sub>@zeolite NaA to Cu<sup>2+</sup> is endothermic, with increasing entropy and spontaneous in nature. The above results show that Fe<sub>3</sub>O<sub>4</sub>@zeolite NaA is a promising Cu<sup>2+</sup> adsorbent.
|
|---|