Biosynthesis of Fe3O4 MNPs from Vicia faba L. peels: promising catalyst for enhanced biogas production from wheat straw

The goal of no waste was considered a very attractive way to recycle waste and extract energy from it on a global scale. Therefore, the primary focus of this study is the biosynthesis of magnetite (Fe3O4) nanoparticles from Green Vicia faba L. peels and analyze their effects on an anaerobic digestion process for biogas production from wheat straw. The structure of biosynthesis of MNPs was characterized using XRD, AFM, VSM, SEM, PSA, and EDX for size resolution and surface morphology. The anaerobic digestion process was carried out on pretreated wheat straw with KOH at mesophilic conditions. To test the activity of prepared NPs, four varying concentrations, namely, 25, 50, 75, and 100 ppm, were dosed for each digester. The revealed results observed that the biogas, methane yields, and intermediate products (TVFA) improved gradually through increasing concentrations of added NPs, and maximum yields were about 250 mL/g(vs), 169.6 mL/g(vs) and 11.95 mg/mL, respectively, when 100 ppm was added.