Sustainable Conversion of Waste Cooking Oil into Biodiesel Through Agricultural Waste-Based Calcium Oxide Catalysis

Abstract

Increasing the demand for sustainable energy and the environmental challenges posed by the use of fossil fuel energy have promoted the generation of bio-fuels. Waste cooking oil (WCO) is a cheap source for the production of biodiesel; however, its efficiency in the biodiesel production process depends on the free fatty acid, moisture content and the reaction conditions. Traditional catalysts tend to incur relatively high costs for processing, chemical usage and recovery. It is, therefore, for this reason that this research focuses on optimizing biodiesel production from waste cooking oil by using CaO catalysts from agricultural wastes. What makes this research unique is the combination of valorisation of agricultural wastes and catalyst preparation to make a process that would economically and environmentally sustain biodiesel production. Agricultural and agro-industrial wastes rich in calcium are collected, cleaned, dried and thermally treated to prepare the CaO catalysts. Properties such as structure, composition, and morphology of the synthesized catalysts are characterized by techniques like X-ray diffraction, Fourier-transform infrared spectroscopy, and scanning electron microscopy. Used cooking oil will be filtered, dehydrated, and, if required, esterified using an acid before transesterification. Reaction parameters such as concentration of the catalysts, methanol-to-oil molar ratio, temperature, and reaction time are optimized using response surface methodology. Properties like yield of biodiesel, efficiency of conversion, reusability of catalyst, and selected properties of the fuel are investigated experimentally. It is anticipated that the planned research approach will show how waste-based CaO catalysts can contribute to efficient use of resources and minimize the dependence on chemical catalysts. The study offers a sustainable approach to convert wasted cooking oil and crop residues to renewable fuel.