Prussian Blue/Silica Nanocomposite for Efficient Removal of Copper(II)from Water

Introduction: Prussian blue (PB) or its analogs is one of the most effective adsorbents for removing heavy metals because of their advantages. Aims: This work aims to develop highly efficient adsorbents for heavy metal removal from contaminated water based on a solid-phase extraction technique. Methods: In this work, the PB/silica nanocomposites were prepared based on the sol-gel technique. The morphology and chemical composition of the synthesized composite were investigated. These nanocomposites were used for Cu(II) removal as they can act as a selective adsorption agent with negligible toxicity. To optimize conditions, the effects of the factor variables (temperature, PB/silica dose, and pH) and their interactions on the adsorption of copper ions were investigated by Response Surface Methodology (RSM) based on Box-Behnken design (BBD). Other experimental parameters (the contact time, and Cu(II) initial concentration) were conducted to determine their effects on Cu(II) adsorption. Results: It was found that the maximum adsorption of 92.30% was obtained at 25°C, 60 minutes of contact time, and 10 ppm of metal ions. It was discovered that the ideal amount of adsorbent material for the removal was 0.1 g L-1. Additionally, the Langmuir isotherm was found to be more suitable for Cu(II) adsorption than the Freundlich isotherm. The kinetic parameters and experimental adsorption capacities for copper onto PB/silica nanocomposites were also studied, and it was found that the system is fitted with pseudo-second-order where the calculated Qe (175.439 mgCu(II)/g) is very close to the experimental Qe (180.697 mgCu(II)/g). Conclusion: Therefore, the newly created environmental nanocomposite material was shown to be appropriate for the adsorption of Cu(II) owing to its elevated adsorption selectivity and capacity, quick adsorption speed, and good regeneration for repeated use for the adsorption of copper pollutants from different water matrices.