Zwitterionic cellulose as a promising sorbent for anionic and cationic dyes

Abstract This work aimed to develop zwitterionic cellulose with a versatile potential for removing anionic and cationic dyes. A grafting degree of 22% in a 3:2 ratio of the anionic and cationic groups was determined by elemental analysis. Spectroscopic characterization by carbon 13 Nuclear Magnetic Resonance (13C NMR) confirmed the zwitterionic functionalization of cellulose. Removal tests showed that zwitterionic cellulose could interact with different dyes (Congo red, Crystal violet, Mordant blue 9, Malachite green, Xylidine ponceau, and Reactive black 5), achieving from 2 to 14-fold of removal at tested conditions.