Untreated effluents from the textile industry containing colorant dyes are harmful to the environment, aquatic organisms, and human health. Among these effluents, Rhodamine 6G is known as a corrosive and irritant dye. A coconut shell-derived nanomagnetic adsorbent composite (CS-NMAC) was developed to remove Rhodamine 6G from aqueous solution. Physical and adsorption properties of CS-NMAC were characterized via Brunauer–Emmett–Teller (BET) surface area analysis (S_BET: 1092.17 m²/g; total pore volume: 0.6715 cm³/g), X-ray diffraction (Fe₃O₄ [θ=35.522], Fe₂O₃ [θ=35.720] and FeO [θ=41.724]) and Fourier transform infrared spectroscopy (Fe–O, C–H, asymmetric C=C=C, CN and O–H). CS-NMAC was found to be electropositive within a broad pH range of 3–10) owing to the presence of nanoscale iron oxides on the surface of the coconut shell-derived adsorbent that enhanced the chemical and electrochemical outputs. Isotherm study revealed that the adsorption process of Rhodamine 6G followed a multilayer type of adsorption onto a heterogeneous surface. Freundlich model fitted better (R² = 0.981) than the other models (Langmuir, Temkin and BET). The maximum adsorption capacity was 32.02 mg/g. Rhodamine 6G removal by CS-NMAC obeyed the pseudo-second-order reaction (R² = 0.9995) as opposed to other kinetic models. CS-NMAC has the potential to become an effective treatment for dye pollution.

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