The present work reports the effect of different functionalization methodologies on surface modification of porous carbon and its efficacy for benzene adsorption. The virgin and surface-modified adsorbents were characterized by FTIR, N2 sorption analysis, SEM, and Boehm titration. The adsorption isotherms were measured at different temperatures using a highly sensitive magnetic suspension microbalance. At lower benzene concentration, the virgin carbon was found to possess reasonable adsorption capacity, while at higher benzene concentration, the surface-modified carbon tends to perform better. The maximum benzene adsorption capacity at 25 °C and vapor pressure of 90 mbar is as follows: 467 mg/g (NORIT-AC), 227 mg/g (AC-APS (1 M)), 388 mg/g (Norit-AC-HT), 492 mg/g (AC-HNO3), and 531 mg/g (AC-H2SO4).

    Abstract
    1 Introduction
    2 Experimental
        2.1 APS treatment
        2.2 HNO3 and H2SO4 treatment
        2.3 Thermal treatment
        2.4 Adsorbent characterization
        2.5 Vapor-phase benzene adsorption
    3 Results and discussion
        3.1 FTIR
        3.2 N2 adsorption–desorption
        3.3 SEM
        3.4 Boehm titration
        3.5 Benzene adsorption
    4 Conclusions
    Acknowledgements 
    References

• Prabhu Azhagapillai(Department of Chemical Engineering, Khalifa University of Science and Technology)
• Ahmed Al Shoaibi(Department of Chemical Engineering, Khalifa University of Science and Technology)
• Srinivasakannan Chandrasekar(Department of Chemical Engineering, Khalifa University of Science and Technology)