Adsorption of Edifenphos pesticide using polypyrrole modified zeolite composite

Today, due to the growing population and increasing agricultural and food production, the use of toxins and organophosphate and organochlorine pesticides, especially Edifenphos, is increasing in the agricultural sector. One of the most effective ways to remove such toxins is to use the adsorption method. Therefore, the present study investigated the removal of Edifenphos fungicide from aqueous solution using polypyrrole composite on natural perlite zeolite. It is notworthy that each experiment was performed in a discontinuous system. For this purpose, after removing possible impurities in perlite through heating at 550 °C and then activating perlite with 0.06 N sulfuric acid, PPy/perlite nanocomposite was prepared. The structure of the adsorbents synthesized was identified using X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. Then, the effect of experimental parameters of pH, contact time, adsorbent mass, and temperature on adsorption was studied. The results showed that the optimal conditions for adsorption of Edifenphos by PPy/Perlite were pH 6, contact time 18 min, and adsorbent amount of 0.3 g/100 ml. Examination of the effect of temperature also showed that increasing the temperature has a positive effect on the removal efficiency. Finally, the study of the process thermodynamics showed a spontaneous and endothermic process.