High Efficiency of Natural Safiot Clay to Remove Industrial Dyes from Aqueous Media: Kinetic, Isotherm Adsorption and Thermodynamic Studies

This study's objective was to demonstrate the potential of Natural Safiot Clay (NSC) for removing cationic dyes MB and Safranin from synthetic wastewater. The operation parameters investigated included initial concentrations, adsorbent dose, initial pH, and temperature. Experimental tests were conducted in a batch process. The experimental isotherms data were analyzed using Langmuir, Freundlich, and Dubinin-Radushkevich isotherm models. The Langmuir model obtained the best fit with a maximum monolayer adsorption capacity of 68.49 mg/g for MB and 45.45 mg/g for safranin. Pseudo-first-order, pseudo-second-order kinetic equations, and intraparticle diffusion models were used to examine the experimental data at different initial concentrations. It was found that the pseudo-second-order kinetic model described the data of dyes adsorption on NSC adsorbent very well. Thermodynamic adsorption processes were found to be spontaneous, exothermic, and physical reactions. The natural safiot clay was characterized using the following technique: DRX, XRF, SEM, EDX, and FT-IR.