Multiwalled carbon nanotubes (MWCNT) decorated by magnetite (Fe3O4) nanoparticles were incorporated into sodium alginate (SA) to fabricate SA-Fe3O4@CNT hybrid membranes. The Fe3O4 nanoparticles were strongly attached onto the MWCNT surface and served as steric barrier to suppress the agglomeration of the MWCNT and improve their dispersion in the hybrid membranes. The synergistic effect of combining Fe3O4 and MWCNT led to both decreasing the membrane crystallinity as well as providing fast-moving micro-channels. After depositing the hybrid membrane (as the active layer) onto the polyacrylonitrile porous support layer, the new composite membranes exhibited excellent separation performance for ethanol dehydration. Using 2 wt% Fe3O4CDCNT as nanofiller, the membrane permeation flux for dehydration of 10 wt% water ethanol feed solution reached as high as 2211 g/m(2) h with separation factor of 1870 at 76 degrees C. (C) 2015 Elsevier B.V. All rights reserved.