Preparation of environmentally friendly activated carbon for removal of pesticide from aqueous media

The preparation of eco-friendly low-cost silkworm feces activated carbon (SFAC) for the removal of oxamyl pesticide from aqueous solution has been investigated in batch experiments. Structure and morphology of SFAC were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), field emission scanning electron microscopy (SEM). The specific surface area and mean pore diameter were obtained as 75.219 and 0.2035 cm^3 g^-1, respectively. The effect of different physicochemical parameters such as initial oxamyl concentrations, activated carbon dose and contact time has been studied. The results showed that the oxamyl removal on SFAC was unaffected in the pH range of 2–10. The percent removal of oxamyl onto SFAC was 99.48% from aqueous solutions. The adsorption process attained equilibrium within 120 min of contact time. Equilibrium data were analyzed by the Freundlich, Langmuir and Dubinin–Radushkevich (D-R) isotherm models. Freundlich isotherm provided the best fit to the equilibrium data. Adsorption kinetic was fitted well by the pseudo-secondorder kinetic model. The results revealed that SFAC could be used a low-cost and eco-friendly alternative to other adsorbents for the oxamyl removal from aqueous solution.