Chitosan/Alginate Nanocomposite with Fe Nanoparticles for the Efficient Removal of Hexavalent Chromium Pollutant.

Biopolymers and nanomaterials are an excellent choice for removing heavy metals and keeping the environment clean. The hexavalent chromium (Cr⁶⁺) (or) chromium-6 is usually produced by various industrial processes, which can be a toxic liquid pollutant. In this study, a nanopolymeric compound supplemented with Fe nanoparticle was used in the extraction (removal) process of Cr⁶⁺ present in the aqueous solutions. Two biopolymers were blended and connected (using a microemulsion process) to produce nanoparticles (Cht/Alg NPs), and the nanoparticles have an average size of 311.2 nm with a negative charge of 23 and 2 mV. During synthesis, the red cabbage extract was also used to make iron nanoparticles (Fe-NPs), and these Fe-NPs had semispherical species with a diameter of 21.4 nm. The nanopolymeric compound was loaded and equally distributed with chitosan and alginate (Cht/Alg) NPs and synthesized Fe-NPs. The assessment using batch adsorption assays showed that both nanocomposites exhibited more ability than the Cr⁶⁺ adsorbents under various conditions (e.g., pH, initial ion concentration, adsorbent volume, and contact time (CT)). At the start, the initial Cr⁶⁺ concentration was 75 ppm, and the most effective adsorption condition was found at 5.0 pH, the adsorbent capacity was 4 g/L, and the CT was 210 min. These documented results show that Cr⁶⁺ may be completely removed from bulk testing. Therefore, the use of these composite nanopolymers (Cht/Alg NPs) combined with the synthesized Fe-NPs can be extrapolated for use in the aquatic milieu for the removal of Cr⁶⁺. [ABSTRACT FROM AUTHOR]