Water-soluble chitosan intercalated montmorillonite nanocomposites for removal of basic blue 66 and basic yellow 1 from aqueous solution

Abstract

Water-soluble chitosan intercalated montmorillonite (wCTS/MMT) nanocomposites were modified and characterized by using Fourier transform infrared, thermogravimetric analysis, and X-ray diffractometer techniques. Two types of wCTS, namely, low molecular-weight chitosan (L-wCTS) and hydroxyethylacryl chitosan (H-wCTS) were synthesized and applied. The batch adsorption experiments on these nanocomposites were conducted by using basic dyes, that is, Basic Blue 66 and Basic Yellow 1 (BY1). The adsorption capacities of sodium montmorillonite (Na-MMT), chitosan, L-wCTS/MMT, and H-wCTS/MMT were measured and compared. The results showed that the adsorption capacities of wCTS/MMT nanocomposites were higher than those values of Na-MMT and chitosan. The adsorption kinetics of wCTS/MMT nanocomposites for BY1 were studied. It was described that the adsorption processes were better fitted by pseudo-second-order equation. The Langmuir and the Freundlich models were used to fit the adsorption isotherm. It was indicated that the adsorption isotherms followed the Langmuir model. The values of the maximum adsorption capacity of L-wCTS/MMT and H-wCTS/MMT adsorbents were at 188.7 and 294.1 mg/g, respectively. © 2012 Wiley Periodicals, Inc.