The investigation of dye adsorption onto Na-bentonite and organo-bentonite

11 ABSTRACT Master of Science Thesis THE INVESTIGATION OF DYE ADSORPTION ONTO Na-BENTONITE AND ORGANO-BENTONITE BİLGE ERDEM Anadolu University Graduate School of Natural and Applied Sciences Chemistry Program Supervisor: Asst. Prof. A. Safa ÖZCAN 2004, 74 pages In this research, the adsorption of Acid Blue 193 (AB193) onto Na- bentonite and surfactant (dodecyltrimethylammonium bromide, DTMA)- modified bentonite was investigated. The adsorption capacities were considerably increased for organo-bentonite obtained from the modification of Na-bentonite. The adsorption was examined by varying the parameters including pH, contact time and temperature. The maximum adsorption of dye was observed at lower pH's. The pseudo-first order and pseudo-second order kinetic models were applied to experimental data and the rate constants were evaluated. According to this, the adsorption of AB193 dynamic data fit well with the pseudo-second order kinetic model. The Langmuir and Freundlich adsorption models were applied to experimental data to describe the equilibrium isotherms and the isotherm constants were then determined. The adsorption of dye onto Na-bentonite and organo- bentonite was agreed very well with Freundlich adsorption model. The thermodynamic parameters were also calculated and interpreted. Keywords: Adsorption, Dye, Kinetics, Clay, Na-Bentonite