Catalytic cracking process of waste cooking oils using iron (Fe) catalysts to produce biofuel

Abstract

Generally, there are 2 (two) methods of converting waste cooking oils into biofuel, namely by esterification of triglycerides into methyl esters (biodiesel), and utilizing thermal cracking of catalysts and hydrogenation to produce green diesel. The presence of oxygen content in waste cooking oils-free fatty acids will cause the formation of CO or CO2 gas during the cracking process, so it is necessary to inject hydrogen to prevent it. In this study, an analysis of operating conditions, the characteristics of the biofuel produced, and the effect of the use of iron (Fe) catalysts were studied to convert used-cooking oil to biofuel. The hydrogenation of waste cooking oil is carried out at pressures of 30 and 40 psia, with heating temperature conditions of 250-350°C and operational pressures of 800-1000 psia. The maximum yield obtained was 31.7% (v) at 350°C and the use of 0.1% wt Fe catalyst. The resulting biofuel had a density of 0.8314 gr/ml and calorific value of 10152.66 cal/gr. By analysis contain of biofuel had C10-C15 5.5%(v), C15-C18 40.27%(v), C18-C20 38.78%(v), and > C20 15.45%(v), respectively.