Adsorption properties of crosslinking carboxymethyl cellulose grafting dimethyldiallylammonium chloride for cationic and anionicdyes

Novel and efficient microspheres adsorbent (MCA-E-0.7/CMC-g- PDMDAAC), based on monochloroacetic acid (MCA) modified epichlorohydrin (ECH) cross-linked carboxymethyl cellulose (CMC), then grafting by dimethyldiallylammonium chloride (DMDAAC), was synthesized and its adsorption properties on cationic and anionic dyes were investigated. The results demonstrated that such MCA-E-0.7/CMC-g- PDMDAAC microspheres showed pH-sensitive and could effectively adsorb cationic dye methylene blue (MB) or anionic dye orange II (OR II), at near neutral (pH > 4) or acidic (pH < 3) condition, respectively. Moreover, it could selectively adsorb the cationic dye MB from the cationic/anionic dye mixture at neutral pH condition. The desorption experiments were mainly performed under acidic (pH 3) or basic (pH 11) condition, over 98.54% of MB and 83.07% of OR II can be desorbed within 20 min, respectively. The pseudo second-order kinetic model and Langmuir isotherm provide better correlation with the experimental data for the adsorption of dyes onto MCA-E-0.7/CMC-g-PDMDAAC microspheres. (C) 2016 Elsevier Ltd. All rights reserved.