Abstract
Activated carbon (AC) was prepared from Diplotaxis acris biomass. The change in the surface functional groups between the biomass raw material and the produced AC was detected using Fourier-transform infrared (FTIR) and Raman spectroscopy. The thermal stability of the prepared AC was determined by using thermogravimetric analysis (TGA). It has a surface area of 40.21 m(2)/g which gave evidence for its external porous surface. The surface porosity and the graphite properties of the prepared AC were detected by scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis, respectively. The amount of adsorbed benzene on the AC surface was determined using a gas chromatograph supported with a flame ionization detector (GC-FID) after extraction in methanol. The adsorption capacity of benzene was 5.4 mg/g at room temperature (25 degrees C), and its removal efficiency reached 95.58% for low benzene concentration (1000 mg/m(3)). The obtained results were well fitted by the Langmuir isotherm model. The adsorption kinetics of benzene followed the pseudo-second-order kinetic model accompanied by the intra-particle diffusion model. The reuse of the AC samples for three consecutive cycles retained the removal efficiency by more than 75% of its original efficiency. Overall, the study revealed that the prepared AC from Diplotaxis acris biomass has a great potential in the removal of benzene from polluted air.