▎ 摘　　要

In the present study, an eco-friendly graphene oxide (GO) were successfully synthesized via singlestep from different agricultural wastes by oxidation under muffled atmosphere condition. The synthesized adsorbents were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscope, and Raman spectroscopy. A simple adsorption method was designed for the removal of Ni(II) by the utilization of GO. The different parameters were optimized such as temperature, concentrations, and time. Among the investigated agricultural wastes, the highest removal of Ni(II) (up to 85.06%) was established for GO obtained from sugarcane bagasse. All the prepared samples from different agricultural wastes showed a good agreement with the Langmuir isotherm model as the obtained regression constant value (R-2) is found to be 0.9. Kinetic studies revealed that the prepared samples are well fitted with the pseudo-second-order due to the surface processes involving chemisorption adsorption of Ni(II). The results showed the applicability of GO obtained from agricultural wastes as a low-cost adsorbent for Ni(II) from aqueous solution.