Adsorption of textile dye Reactive Red 120 by the chitosan-Fe(III)-crosslinked: Batch and fixed-bed studies

This paper presents a study of the use of chitosan-iron(III) crosslinked with glutaraldehyde (Ch-Fe) as an adsorbent for the textile anionic dye Reactive Red 120 (RR120) in batch and fixed-bed systems. The maximum adsorption capacity was calculated from the adsorption isotherms, and well fitted by the Langumir-Freudlich isotherm model. The process followed the kinetic model of pseudo-second-order. In fixed-bed studies, the Thomas, Adams-Bahort and Clark models were applied to the breakthrough curves. The thermodynamic parameters showed that the adsorption process is spontaneous and favorable. The adsorbent can be easily regenerated and reused. The adsorption of the RR120 was optimized using a 3(3) factorial design, and the initial pH of the dye solution had a significant effect. (C) 2013 Elsevier Ltd. All rights reserved.