Optimization Removal of the Ceftriaxone Drug from Aqueous Media with Novel Zero-Valent Iron Supported on Doped Strontium Hexaferrite Nanoparticles by Response Surface Methodology

The present study, a novel and efficient adsorbent nano zero-valent iron stabilized on strontium hexaferrite (nZVI/SrFe12O19) was synthesized for removal of ceftriaxone antibiotic from aqueous solution. Its characteristics were analyzed by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX). Response Surface Methodology (RSM) based on Box-Behnken Design (BBD) were used to achieve the optimal experimental conditions. The effects of parameters such as pH (5-9), initial concentration of ceftriaxone (5-15 mg L-1), and adsorbent dosage (0.05-0.15 g L-1) on removal efficiency were investigated. A mathematical model was studied to predict the removal performance. The significance and adequacy of the model were surveyed using analysis of variance (ANOVA). The results showed that second-order polynomial model is suitable for the prediction removal of ceftriaxone. The highest removal value of mentioned drug were obtained 98 % at adsorbent dosage of 0.15 g L-1, pH=5, and the pollutant concentration of 10 mg L- 1. Finally, the isotherms and kinetic studies were evaluated. The Langmuir with R-2=0.9981 and pseudo-second-order with R-2=0.9996 were the best isotherm and kinetic, respectively. The thermodynamic parameters such as Delta H-0, Delta S-0, and Delta G(0) were calculated and it was indicated that adsorption process was exothermic and spontaneous.