Nano-iron-modified pomegranate peel powder for rapid and recyclable removal of acetaminophen
摘要
Pharmaceuticals such as acetaminophen are increasingly detected in the aquatic environment and represent a persistent risk to ecosystems and human health. This study reports the fabrication of nano-iron-loaded pomegranate peel powder (NIL-PP)and its application as a low-cost, magnetically separable adsorbent for the removal of acetaminophen (ACT) from aqueous solutions. Successful loading of nanoscale iron species onto the bio-char matrix was confirmed by SEM-EDS, XRD (average crystallite size is 14 nm), FTIR, BET, TGA, and VSM (18.5 emu/g), indicating a heterogeneous, porous, and magnetically responsive adsorbent. Batch adsorption results indicated that the kinetic data are best described by the pseudo-second-order model, while the equilibrium data fit well with the Freundlich isotherm, suggesting that the adsorption process is predominantly governed by chemisorption occurring as multilayer coverage on energetically heterogeneous surface sites. The optimal removal was observed at an adsorbent dosage of 1 g/L, near neutral pH, an initial ACT concentration of 15 mg/L. The removal rate of ACT exceeded 95.29% within 180 min. Thermodynamic analysis indicates the adsorption is exothermic (ΔH° ≈ −47.13 kJ/mol) and proceeds with overall spontaneous behaviour under test conditions. The NIL-PP material retained a substantial fraction of its capacity (64.33%), even after four consecutive cycles and can be readily separated from water by magnetic collection. This result from this work emphasize the potential of NIL-PP as a suitable adsorbent to be used on a large scale for the environmental remediation of pharmaceutical pollutants in an environmentally sustainable and economically viable manner.