Surface modification of coconut shell based activated carbon for the improvement of hydrophobic VOC removal

► Coconut shell based carbons were chemically treated by alkalis and acids. ► GAC modified by alkalis had better o-xylene adsorption capacity. ► We analyzed textural and surface chemistry changes induced on the GAC. ► Reducing hydrophilic carbon surface favors abatement of hydrophobic VOCs. ► Reducing hydrophilic carbon surface results in less adsorbent regeneration.