Comparison of Phenolic Contaminants Removal from Aqueous Solution by Grafting of Allyl Glycidyl Ether-Allyl Alcohol onto Zinc Sulfide Nanoparticles

Abstract

This work comparatively evaluated the removal efficiency of nonylphenol (NP) and bisphenol A (BPA) from aqueous solutions by zinc sulfide nanoparticles (ZnS NPs) functionalized with allyl glycidyl ether (AGE) and allyl alcohol (AA). The characterization techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy with energy dispersive spectrometer (FE-SEM/RDX), and thermogravimetric (TG) analyses were applied to compare the crystal structure, functional groups, shape change and elemental composition and the thermal behavior, respectively. The conditions for the removal of NP and BPA were predicted using the response surface methodology (RSM) via the central composite design (CCD). The effects of pH (A: 3–9), temperature (B: 20–40 °C), and contact time (C: 10–30 min) were examined using an experimental design. Using the optimized condition (pH = 6, temperature = 20 ºC, and contact time = 20 min), their sorption capacity of them reached 15.32 and 32.58 mg g⁻¹, respectively, and the removal efficiency of NP and BPA reached 96.26 and 85.11%, respectively. Among the isotherm models, Langmuir in non-linearized forms was well fitted for both pollutants (NP; R² > 0.9956, SSE = 0.600 and BPA; R² > 0.9917, SSE = 0.310). Kinetic studies shown that, pollutants adsorption complied with pseudo-second-order kinetic models (BPA; R² > 0.9995, SSE = 0.150 and NP; R² > 0.9995, SSE = 0.08). The capability analysis of the RSM-CCD model was investigated using the correlation coefficient and some statistical error functions such as the average relative error (ARE), root mean square error (RMSE), Hybrid Fractional Error Function (HYBRID), and the Chi-square test (χ²). It was observed that nanoadsorbent could be commonly applied for NP and BPA removal up to eight and nine times without noticeable decrease in its removal efficiency, respectively. According to the obtained data, it can be shown that the nanoadsorbent has an appropriate ability to remove phenolic compounds from aqueous solutions, which suggests promising perspectives for its practical application in pollutant treatment scenarios.