Removal of Cr(III) Ions from Water Using Magnetically Separable Graphene-Oxide-Decorated Nickel Ferrite Nanoparticles

Abstract

Removing toxic metal ions from water is a challenging task due to the increasing demand for potable water worldwide. Utilization of an efficient adsorbent has been the key strategy for addressing this issue. However, the adsorbents utilized so far, whether carbon-based or silica-based, present difficulties in separation from water and pose a harm to aquatic life. In this study, we present a novel approach involving the fabrication of well-dispersed NiFe2O4 nanoparticles, averaging approximately 7 nm in size, integrated with graphene oxide. This nanocomposite proves to be highly effective in removing Cr(III) ions from water. At room temperature, it exhibits a superparamagnetic behavior, enabling easy magnetic separation of the adsorbent from the water. By utilizing the nanocomposite, we achieved a removal rate of approximately 17 mg/g for Cr(III) ions dissolved in water. This ensures that their concentration in the water remains below the EPA-prescribed permissible level of 0.1 mg L–1. Additionally, we propose a simple and cost-effective optical method for detecting Cr(III) ions in water. This innovative approach shows great promise in tackling the challenge of toxic metal ion removal from water, offering an efficient and environmentally friendly solution.