Polymeric ferrite composites as versatile adsorbents for enhanced reactive blue dye removal: a promising solution for treating textile wastewater

Water contamination caused by the increasing industry and urbanisation is one of the most significant environmental problems that entire planet is facing. Various polymeric ferrite composites synthesised in the current study were employed to remove the synthetic reactive dye blue-248 from wastewater. The polymeric ferrite composites were characterised using scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transmission infrared spectroscopy (FTIR) to observe the surface morphology, crystallinity and chemical structure of as-prepared composites. The optimum removal of dye using Ni-CoFe₂O₄/Chitosan, Zn-NiFe₂O₄/Starch, CoNiZnFe₂O₄/Polyaniline, Ni doped CrZnFe₂O₄/Alginate, Cr doped ZnCoFe₂O₄/PVA was at (i) pH 2 (32.34 mg/g), 3 (30.31 mgg⁻¹), 3 (21.05 mgg⁻¹), 3 (25.69 mgg⁻¹) and 4 (38.61 mgg⁻¹), (ii) optimum dose (0.03 mg/g) 32.40, 30.27, 21.91, 25.98 and 39.2 mg/g, (iii) Contact time (6090 min) 46.898, 37.70, 43.318, 29.356 and 34.12 mg/g, (iv) Initial dye concentration 32.24 mgg¹, 25.79 mgg⁻¹ (120 mg/L), 35.85 mgg⁻¹, 28.37 mgg⁻¹ and 40.37 mgg⁻¹ (150 mg/L) and (v) temperature (65°C) 29.67, 27.08, 21.66, 23.60 and 41.40 mg/g, respectively. Different equilibrium, kinetic and thermodynamic models were used to check the nature of sorption, reaction rate/order of reaction and feasibility of reaction, respectively. The effect of presence of various electrolytes, different metals and surfactants in wastewater were also studied. For dye removal on a large scale, the effects of bed height (1–3 cm), flow rate (1.8–5.4) and initial dye concentration (50–90 ppm) were examined in column study. Different eluents were used for the desorption study of reactive dyes to check the reusability of process.