2⁴ Factorial Design Optimization of Process Variables for Biodiesel Production from Waste Cooking Oil
Received: 30 September 2025 | Revised: 13 January 2026 | Accepted: 19 January 2026 | Online: 4 April 2026
Corresponding author: Ong Riyanto
Abstract
The increase of global population, leads to greater energy demand, causing resource depletion, increased emissions, and environmental degradation. The production of biodiesel from Waste Cooking Oil (WCO) offers a promising solution. However, optimizing WCO biodiesel often requires costly and complex processes such as advanced photocatalysts, microwave heating, or membrane reactors. This study uses a 2⁴ factorial experimental design to improve WCO biodiesel production based on ASTM specifications, resulting in a 96% biodiesel output at the following conditions: 40 °C, 30 min transesterification, 0.5% catalyst, and a 12:1 alcohol-to-oil molar ratio. The measured fuel properties—specific gravity, kinematic viscosity (at 40 °C), acid number, sulfated ash content, cloud point, flash point, distillation temperature, copper corrosion resistance, carbon residue content, iodine value, methyl ester content, monoglyceride content, free glycerol content, and total glycerol content—show that high-quality biodiesel can be produced from WCO under simple and economically viable conditions.
Keywords:
biodiesel, energy, optimization, transesterification, waste cooking oilDownloads
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