Adsorption of malachite green from aqueous solution by using novel chitosan ionic liquid beads

Chitosan ionic liquid beads wereiprepared from chitosan and 1-butyl-3-methylimidazolium based ionic liquids to remove Malachite Green (MG) from aqueous solutions. Batch adsorption experiments were carried out as a function of initial pH, adsorbent dosage, agitation time and initial MG concentration. The optimum conditions were obtained at pH 4.0, 0.008 g of adsorbent dosage and 20 min of agitation time were utilized in the kinetic and isotherm studies. Three kinetic models were applied to analyze the kinetic data and pseudo-second order was found to be the best fitted model with R-2 > 0.999. In order to determine the adsorption capacity, the sorption data were analyzed using the linear form of Langmuir, Freundlich and Temkin equations. The isotherm was best fitted by Langmuir isotherm model. The maximum adsorption capacity (q(max)) obtained from Langmuir isotherm for two chitosan beads 1-butyl-3-methylimidazolium acetate A and 1-butyl-3-methylimidazolium B are 8.07 mg g(-1) and 0.24 mg g(-1) respectively. (C) 2017 Elsevier B.V. All rights reserved.