An Evaluation of the Adsorption Potential of MWCNTs for Benzene and Toluene Removal

In order to evaluate the adsorption potential of multi-walled carbon nanotubes (MWCNTs) for benzene, toluene and xylenes (BTX), the adsorption capacities of benzene and toluene on two different MWCNTs were measured using a gas-chromatography (GC) and then compared with each other. Fourier transform infrared (FTIR) was employed to investigate the presence of functional groups on the carbon nanotubes surface. The MWCNTs were also characterized by Raman spectroscopy and scanning electron microscopy (SEM) techniques and their specific surface areas were determined using the Brunauer–Emmett–Teller (BET) method. FTIR spectra proved the presence of functional groups on the surface of both two different MWCNTs. Generally, the results revealed that the MWCNTs with larger specific surface area and higher crystallinity have higher adsorption capacities for both benzene and toluene. Moreover, as compared with conventional adsorbents like the activated carbon, the carbon nanotubes have the advantages such as selectivity to aromatic volatile organic compounds such as BTX.