Magnetically Modified Carbonized Plant-Derived Sorbents for Efficient Oil Adsorption and Recovery
Abstract
The elimination of organic pollutants and oil spills remains one of the major environmental challenges of our time. Among the various remediation techniques, the sorption method is considered the most efficient for removing oil from water surfaces. In this study, organophilic carbon-based oil adsorbents were synthesized via carbonization of plant-derived raw materials, peanut shells and walnut wood, in an argon atmosphere at 600 °C. Additionally, magnetite-modified carbonized composites of these materials were prepared. The adsorbents were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) surface area analysis, and Barrett–Joyner–Halenda (BJH) pore size distribution. FTIR spectra confirmed the presence of Fe–O bonds, indicating successful incorporation of magnetite within the composites. The formation of magnetite in the pores of the carbon matrix resulted in a reduction of specific surface area, from 1696.20 m2/g to 1053.47 m2/g for peanut shell carbon, and from 1533.60 m2/g to 1033.91 m2/g for walnut wood carbon. Oil adsorption studies revealed adsorption capacities of 3.8 g/g and 3.6 g/g for the carbonized peanut shell and walnut wood, respectively, and 4.3 g/g and 4.8 g/g for their corresponding magnetite composites. The enhanced oil adsorption performance of the magnetic composites is attributed to an increased proportion of macropores (50–200 nm), which facilitate oil uptake in emulsion systems.