Green synthesis of copper oxide nanoparticles using Punica granatum leaf extract applied to the removal of methylene blue

Abstract The study proposed a method of obtaining copper oxide nanoparticles through green synthesis using pomegranate leaf for application in the adsorption of methylene blue. The synthesized material was characterized. The kinetic data fitted to pseudo-second-order and the intra-particle diffusion model, which showed three steps: film, intra-particle diffusion and equilibrium. The equilibrium data fitted to the Langmuir model, resulting in the maximum adsorption capacity of 166.021 mg g−1 at 318 K. Also, the thermodynamic parameters indicated a spontaneous, endothermic and reversible process. The results showed a high efficiency of the proposed adsorbent, obtaining up to 96.91% of removal.