Investigation of isotherm and thermodynamic parameters of adsorption of copper (II) ions in aqueous solution with natural mixed type Siirt clay (NMTSC-2) and new (second) linear equation derived from Harkins-Jura isotherm

Abstract

In this study, it was aimed to remove Cu (II) ions from the aqueous solution by Natural Mixed Type Siirt Clay (NMTSC-2) from the aqueous solution. NMTSC-2 (clay containing chlorite, montmorillonite, vermiculite, muscovite, kaolinite and illite) was characterized by analysis methods of X-ray fluorescence spectroscopy (XRF), Fourier transform infrared, (FT-IR) spectroscopy, X-ray diffraction (XRD), field emission scanning electron microscope (FESEM-EDS), Brunauer-Emmett-Teller (BET) and thermogravimetric analysis (TGA). The data obtained as a result of the experimental studies were applied to the Freundlich, Langmuir, Temkin, Elovich and Dubinin-Radushkevich (D-R), Harkins-Jura adsorption isotherms. In the study, a new linear equation was derived from the Harkins-Jura model. The new form was applied to the NMTSC-2 adsorption experiment of Cu (II), the obtained constants and the plots were given in the study. In order to compare the models, the results were subjected to regression analysis. The new linear equation was found to be the most suitable model for the experimental data. The Langmuir model was the second most compatible with the experimental data. In adsorption experiments were performed at 298, 308 and 318 K temperatures, Cu (II) ion qm values were found as 21.146, 25.380 and 29.850 mg g-1, respectively. Thermodynamic data for 298,308 and 318 K temperatures were found as Delta G = - 24.394, - 33.724 and - 43.054 kJ mol-1 Delta H = 53.039 kJ mol-1, Delta S = 0.181 kJ mol-1 K-1.