Experimental Investigation of Methane Generation in the Presence of Surface and Un-Surface Nanoparticles of Iron Oxide

Abstract

The exploitation and harnessing of renewable energies are becoming increasingly important throughout the world. This study presents a method of methane (CH4) generation using biological disintegration of food waste (FW) by anaerobic digestion (AD). The CH4 production was enhanced by the addition of three different types of iron oxide (Fe3O4) nanoparticles (NPs) (Cetyletrimethlebromide (CTAB), urea-capped Fe3O4 NPs and Fe3O4 NPs without capping). The bio generation of CH4 and biodegradation of volatile solids (VS) were carried out in an AD treatment at mesophilic conditions (35–37 °C) for more than 50 days in batch mode. The concentration of all three types of NPs was kept constant at 75 mg/L. It was noticed that urea-capped NPs produced the maximum CH4 (5.386 L), followed by Fe3O4 NPs (5.212 L). Methane production in the control bioreactor was 2.143 L. The experimental results of CH4 generation (a dependent variable) were analyzed against the concentrations of NPs used (as independent variables) in multiple regression analysis (MRA). The overall model for the experiments resulted in R2 and R-adjusted values of 0.995 and 0.993, respectively.