Effect of Ni-Ferrite and Ni-Co-Ferrite nanostructures on biogas production from anaerobic digestion

Many Nanoparticles (NPs) were reported to significantly enhance the production of biogas from the anaerobic digestion of organic wastes. Herein, two types of NPs (Ni-Ferrite and Ni-Co-Ferrite) were synthesized using the co-precipitation method and characterized using X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM) with energy dispersive X-ray spectroscopy (EDS) techniques. Three different concentrations (20, 70 and 130 mg/l) of each type were added to separate biogas reactors to study their effect on the biogas production compared to blank reactor. A pressure-based biogas reactor was designed and manufactured specifically to test the effect of the NPs on the anaerobic digestion process. The pressure of the daily produced biogas was monitored using a pressure transducer and the volume of the biogas was calculated at standard conditions of pressure (1.013 bar) and temperature (15 °C). The results showed an increase in the biogas production of 6.6%, 5.9% and 32.9% upon the use of Ni-Co-Ferrite NPS at concentrations of 20, 70, and 130 mg/l compared to blank reactor, respectively. In addition, the Ni-Ferrite NPs achieved biogas enhancements of 30.8%, 28.5%, and 17.9% at concentrations of 20, 70 and 130 mg/l, respectively.