Abstract:

This study investigates the usability of FeCl3 nanoparticles synthesized with tea waste by green synthesis method as an adsorbent in the removal of methyl violet 2B, a widely used cationic dyestuff, from wastewater. Characterization analyzes of FeCl3 nanoparticles synthesized with tea waste were performed with SEM/EDX and FTIR. pH, adsorbent dose, initial dyestuff concentration parameters were studied in batch system and optimum conditions were determined. According to the experimental results, the best adsorption efficiency was obtained at the pH of 4.5, adsorbent dose of 1 g/L and initial dyestuff of 50 mg/L. Equilibrium data obtained using different initial dyestuff concentrations and temperatures were applied to the Freundlich, Langmuir, Dubinin-Radushkevich and Temkin adsorption isotherms. The experimental results best fitted to the Langmuir isotherm. The separation factor (RL) calculated using Langmuir isotherm equations is between 0 and 1 at all temperatures, also showing that adsorption fits the isotherm. In kinetic studies, experiments were performed at an initial dye concentration of 50 mg/L and the adsorption was found that adsorption was in fiting the pseudo second order kinetic model. Negative ΔG values (-5.703, -5.226, -5.148 kj/mol) determined in thermodynamic studies showed that adsorption was spontaneous and feasible. A negative ΔH value (-13.898 kj/mol) means adsorption is exothermic. It has been shown that FeCl3 nanoparticles synthesized with tea waste can be used as an effective adsorbent in the removal of methyl violet 2B from aqueous solutions with approximately 80% efficiency.

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