Optimizing Energy Conversion in Waste Cooking Oil Pyrolysis with a Low-Cost Carbonaceous Catalyst Using Response Surface Methodology
Abstract
The objective of this study was to determine the optimal conditions for converting waste cooking oil (WCO) into bio-oil via pyrolysis with activated carbon (AC) using response surface methodology (RSM). A central composite design was employed to model the relationship between reaction temperature, AC to WCO ratio, and Brauer-Emmett-Teller (BET) surface area and their effects on bio-oil yield and energy conversion. The analysis of variance identified reaction temperature as the most influential factor. The optimal conditions for maximum energy conversion (93.41%) were found to be a temperature of 425 °C, an AC to WCO ratio of 1:40, and a BET surface area of 758 m2/g. In contrast, under conditions with a BET surface area of 1000 m2/g, the energy conversion was 88.14%, which was the highest energy conversion observed in the experiment. Under this condition, the bio-oil contained over 40% diesel-like compounds. However, due to its high acid value, the bio-oil is not directly usable in diesel engines without further treatment.