THE ADSORPTION OF BASIC RED 46 ON THE NATURAL MINERAL LIMESTONE WITH MONTMORILLONITE

Abstract

The purpose of this study is to investigate the applicability of the natural mineral limestone withmontmorillonite as an adsorbent, and the removal of Basic Red 46 (BR 46) which is used textile industryand given to receiving waters with wastewaters. The optimum environmental conditions in theadsorption of BR 46 on MKT were determined as initial pH 8.0, temperature 25 o C and adsorbentconcentration 1.0 g/L; it was observed that the adsorbed amounts increased linearly with concentration(q d =0.8*Co ; R2 =0.9965) in the studied initial concentration range. Langmuir, Freundlich, Temkin,Dubinin-Radushkevich isotherm models were applied to equilibrium data and it was concluded that theequilibrium data fitted better to Langmuir isotherm model. The maximum BR 46 adsorption capacity ofMKT was determined as 169.5 mg/g. Experimental kinetic data fitted to the pseudo second orderreaction kinetic, it was concluded that the intraparticle and external diffusion was effective in the studiedadsorption process. According to the thermodynamic parameters, such as free Gibbs energy, enthalpy, entropy changes,it was determined that the adsorption of BR 46 on MKT was exothermic and spontaneous in nature. Thecharacterization studies of MKT before and after adsorption were carried out with FTIR, SEM and XRDanalyses.