Optimization of acetaminophen adsorption onto biodegradable waste-derived activated carbon using response surface methodology

In this study, biodegradable waste like banana peel was used as a precursor for synthesis of activated carbon by the use of acidic chemical process. The activated carbon was impregnated with iron oxide for acetaminophen removal from water. Scanning electron microscope (SEM) analysis, X-ray diffraction (XRD) analysis and Brunauer-Emmet-Teller (BET) analysis were performed to characterize the iron oxide impregnated activated carbon. The SEM results denote the presence of macropores, while from the XRD it was evident that the synthesized activated carbon contains “Maghemite” (γ-Fe2O3) and “Magnetite” (Fe3O4). Specific surface area of 268.52 m2/g, and pore volume of 54.3 cc/g was obtained from BET results. Response Surface Methodology was used to optimize the adsorption process of aqueous solutions of acetaminophen using the following parameters: adsorbent dosage (0.5–1 g/L), pH (4–6), initial concentration of Acetaminophen (50–100 ppm) and time (60–120 min). Central Composite Design was employed to conduct a set of 31 runs and ANOVA was used to determine the priority of the parameters in the adsorption process. The optimum values of the parameters for 94.7 % removal efficiency of acetaminophen are, adsorbent dosage at 0.97 g/L, pH at 3.48, initial concentration at 58.3 ppm, and time at 120.9 min. The R2 value of the regression equation was determined to be 95.06%.