Akademik Veri Yönetim Sistemi
POLYMER BULLETIN, cilt.80, sa.3, ss.2585-2615, 2023 (SCI-Expanded)
Synthesis of low-cost and high adsorption capacity adsorbents is extremely important in the removal of diclofenac sodium, which is among the nonsteroidal anti-inflammatory drugs and has a toxic effect in wastewaters. In this study, we synthesized a composite with Ppy to improve the adsorption capacity of the zeolite. Polypyrrole (Ppy) and Ppy/zeolite used as adsorbents in diclofenac sodium (DCF) removal were synthesized by chemical oxidation method. Characterizations of synthesized Ppy and Ppy/zeolite adsorbents were investigated using Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX) and thermogravimetric analysis (TGA) methods. The effects of DCF initial concentration change, pH (6 and 9) and temperature (293 K, 303 K and 313 K) on the removal of DCF by adsorption were investigated. The adsorption mechanism of both adsorbents was investigated with Langmuir, Freundlich and Dubinin-Radushkevich (D-R) adsorption isotherm curves, and the adsorption reaction kinetics were explained using pseudo-first- and second-order kinetic models. In addition, the thermodynamic parameters (Delta G, Delta S and Delta H) of the DCF adsorption reaction were calculated. According to the experimental results obtained, the adsorption mechanism in DCF removal was explained by Langmuir adsorption isotherm by using Ppy and Ppy/zeolite as adsorbents, while the conformity of the reaction kinetics to the pseudo-second-order reaction rate model was determined. In addition, the calculated Delta G values indicate that the adsorption reaction occurs spontaneously, and the Delta H values indicate that the reaction is exothermic. As the temperature increased, the maximum absorption capacity decreased. Consequently, it was determined that DCF adsorption efficiency was high with the use of very small amounts of Ppy and Ppy/zeolite.