| Abstract |
The increasing global demand for phosphate fertilizers has led to a significant accumulation of phosphogypsum, a calcium sulfate by-product generated during phosphate fertilizer production. The improper management of phosphogypsum stockpiles can pose environmental risks. Similarly, aluminum foil is a commonly discarded postconsumer waste with limited reuse options. In light of these challenges, this study presents a novel and innovative approach for the synthesis of hydrocalumite from these wastes and evaluating its effectiveness in removing Acid Red 97 dye. various characterization techniques including Scanning electron microscopy (SEM), Energy-Dispersive X-Ray Spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) were employed to analyze the properties of the synthesized material. The performance of CaAl-Cl was evaluated through batch adsorption experiments, considering factors such as pH, adsorbent dosage, and contact time. By carefully optimizing these parameters, the study successfully identified the optimal conditions, resulting in an impressive maximum adsorption capacity of 1019.97 mg/g at room temperature and pH 5.8. The findings indicated that the adsorption process followed the pseudo second order kinetics. Additionally, the Sips isotherm model provided the best fit to the experimental data, suggesting multilayer adsorption with heterogeneous surface energies. Furthermore, the thermodynamic parameters indicated that the adsorption process was exothermic, spontaneous, suggesting physisorption as the dominant mechanism. Overall, this study demonstrates the potential of hydrocalumite synthesized from phosphogypsum and aluminum foil as a sustainable, low-cost adsorbent for dye removal applications. This offers an eco-friendly solution for reducing industrial waste streams while providing environmental protection through water treatment. With further optimization, this approach shows promise for enabling the circular economy of phosphogypsum on a larger scale. |