WASTE COOKINGOIL

With the increasing global demand for sustainable and renewable energy, biodiesel has becomean essential alternative to traditional fossil fuels. This study looks into producing biodiesel fromwaste cooking oil (WCO) by using a unique catalyst made from calcined periwinkle shells. The WCO was characterized to uncover its main properties using ASTMD6751 standardmethodand the catalyst was produced through calcination at 900°C. The transesterification process wasoptimized using Response Surface Methodology (RSM) with a Box-Behnken design, usingfactors like catalyst loading (1–10 wt.%), reaction time (30–150 minutes), temperature(40–80°C), and the molar ratio of alcohol to oil (3:1–10:1). The result obtained from the characterization of the WCO are acid value of 6.17 mg KOH/g, a free fatty acid (FFA) content of 3.09%, a viscosity of 9.2 mPa.s at 30.08°C, a saponification value of 244.14 mg KOH/g, and a density of 956 kg/m³. The analysis of the calcined periwinkle shell show that it contains a high amount of calcium oxide (CaO) of about 97.08%, as revealed by Energy Dispersive X-ray (EDX) analysis. Additionally, Fourier Transform Infrared Spectroscopy (FTIR) confirmed the existence of functional groups necessary for biodiesel production, while Scanning Electron Microscopy (SEM) showed a highly porous structure, which significantly improved its catalytic efficiency. With the optimized conditions, a biodiesel
yield of over 90% was achieved. The final biodiesel product met industry standards and exhibited enhanced physicochemical properties.