Effect of time on alternative hydrocarbon production from waste PS with biodiesel of candlenut oil using catalytic cracking and Si/Al-Ceramic as catalyst

In the present study, the catalytic cracking process of polystyrene (PS) plastic waste and biodiesel of candlenut oil was carried out using Si/Al-ceramic catalyst with a mass ratio of 7:3 at 300 °C. This study aimed to investigate the effect of reaction time on the distribution of hydrocarbon fuel fractions produced. They are characterized by XRD, SEM-EDX, FTIR, and N2 gas adsorption-desorption. The products components of PS catalytic cracking were analyzed by gas chromatography-mass spectroscopy (GC-MS). The liquid fuel obtained was mixed with commercial fuel, Premium RON 88, and methyl tertiary butyl ether (MTBE) additive to determine its physicochemical properties and performance in a generator engine with gasoline-based fuel. The result showed that an increase in reaction time from 60 minutes to 120 minutes of PS cracking over Si/Al-Ceramic catalyst leads to the enrichment of long-chain hydrocarbon fraction (> C12) by 25.61% which is attributed to the formation of styrene dimer. The fuel has thermal efficiency of 26.49% with density of 0.7405 g/cm3, flashpoint of < -50 °C, calorific value of 9642.42 kcal/kg, and octane number of 92.2. These characteristics are in accordance with SNI 06-3506-1994 standard. Therefore, liquid fuel from catalytic cracking of polystyrene plastic wastes can be used as a potential alternative fuel in the gasoline range.