Abstract
As global demand for fossil fuels rises amidst depleting reserves and environmental concerns, exploring sustainable and renewable energy sources has become imperative. This study investigated the pyrolysis of corncob, a widely available agricultural waste, using urea as a catalyst to enhance bio-oil production. The aim was to determine the optimum urea concentration and pyrolysis temperature for bio-oil yield from corncob. A series of experiments were conducted at varying temperatures (350 °C, 400 °C, and 450 °C) and urea concentrations (0%, 5%, 10%, 15%, and 20%) to assess their impact on bio-oil yield, chemical composition, and energy content. Fourier Transform-Infrared Spectroscopy, Gas Chromatography-Mass Spectrometry (GC-MS), Ultimate Analysis, and High Heating Value (HHV) analyses were employed to evaluate the quality of bio-oil produced. Results indicate that a 10% urea concentration at 400 °C improves bio-oil yield from 49.33 to 54.66%. FT-IR analysis revealed enhanced absorption in key functional group regions, including O-H, N-H, C-H, C=O, and C-O, for bio-oil treated with 10% urea compared to untreated bio-oil. Ultimate analysis indicates that urea treatment improved bio-oil quality by increasing carbon (84.80-86.40%), nitrogen (2.29-2.68%), and oxygen (7.22-8.31%) contents while reducing hydrogen (5.09-2.38%) and sulfur (0.62-0.20%) contents, with improvement in the HHV from 36.12 to 37.12 MJ/kg. GC-MS analysis further revealed the presence of nitrogenous compounds, notably siloxanes in the bio-oil produced with urea infusion. This research highlights the potential of urea-catalyzed pyrolysis as a viable method for converting corncob into high-energy bio-oil, offering a promising alternative to traditional fossil fuels while addressing sustainability and environmental impact challenges.