Enhanced removal of amoxicillin and chlorophenol as a model of wastewater pollutants using hydrogel nanocomposite: Optimization, thermodynamic, and isotherm studies

Studies have been conducted to gain understandings and generic knowledge of the equilibrium aspects of adsorption of different adsorbents, SA-Bn-TiO2 NPs surfaces. Removal of two pollutants, Amoxicillin drug AMX, 4-chlorophenol (CPH) from aqueous solutions by adsorption with SA-Bn-TiO2 NPs, SA-Bn and TiO2 NPs surfaces were experimentally determined. The best results were found at pH 6.6, temperature 30 ºC, and adsorbent dosage of 0.05 g of SA-Bn-TiO2 NPs for both studying adsorption capacity and removal percentage. The morphology and structure of the SA-Bn-TiO2 NPs hydrogel beads were investigated utilizing Ultraviolet-Visible Spectroscopy (UV–Vis), Fourier Transform Infrared (FT-IR), Thermo gravimetric analysis (TGA), Field Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM), Energy Dispersive X-Ray (EDX) and X-ray Diffraction Spectroscopy (XRD). The best contact time for equilibrium reached one hour. It is essentially due to saturation of the active site which does not let further adsorption to take place. For the two pollutants onto hydrogel, best adsorption was found to be at pH 11, and adsorption raised by increase in the pH solution. The value negative of ∆G confirmed that the nature adsorption process is spontaneous. The value positive of ∆S confirmed the raise randomness at the solid-solution interface pending adsorption and the value positive of ∆H confirmed that adsorption process is endothermic.