Preparation of Fe/activated carbon directly from Orange Peel and its application in removal of nitrate from aqueous solutions

In this study activated carbon was synthesized from orange peel by ZnCl2 solution at 60 ºC for 12 h and then carbonized in a furnace at 475 ºC for 90 min. The treated sample was impregnated with iron (III) chloride solution in the presence of NaBH4 solution under a nitrogen atmosphere. The samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). The effects of various parameters such as pH, contact time, initial nitrate concentration, and adsorbent dosage were investigated for efficient removal of nitrate. The results showed impregnation activated carbon with Fe improved the adsorption ability by nearly two times more compared to the pure one. Kinetics data indicate that the adsorption of nitrate follows pseudo-second order kinetics model. The adsorption data are found to fit well with Langmuir isotherm and the maximum adsorption capacities for activated carbon and Fe/ activated carbon were obtained 16.23 and 41.32 mg/g, respectively.