Multiwall carbon nanotubes (MWCNTs) have attracted multidisciplinary interest because of their special physicochemical properties. Herein, plasma technique was applied to graft chitosan (CS) on MWCNTs to improve their dispersion property and sorption ability for polychlorinated biphenyls. The CS grafted oxidized MWCNTs (MWCNT-g-CS) was analyzed by using Fourier Transform Infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD), UV-vis spectrophotometry, thermogravimetric analysis (TGA)-differential thermal analysis (DTA), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), and the results indicated that CS was successfully grafted on the surfaces of MWCNTs. The prepared MWCNT-g-CS was applied to remove 4,4'-dichlorobiphenyl (4,4'-DCB) from aqueous solution under ambient conditions. The results showed that MWCNT-g-CS was a suitable material in the preconcentration and immobilization of 4,4'-DCB from large volumes of aqueous solutions in polychlorinated biphenyl pollution cleaning. (C) 2010 Elsevier B.V. All rights reserved.