Energy & Fuels, Vol.21, No.6, 3076-3083, 2007
Modeling and simulation of transport riser reactor for catalytic cracking of palm oil for the production of biofuels
The catalytic cracking of palm oil over rare earth-Y (REY) catalyst for the production of biofuels in a transport riser reactor at atmospheric pressure, temperature of 673-773 K, catalyst-to-oil ratio (CTO) of 5-10, is reported. The cracking was studied at different residence times and axial reactor lengths. In the present study, palm oil-based fatty acid mixture (FAM) cracking kinetics was found to be similar to the cracking kinetics of palm oil, because both FAM and palm oil consist of different fatty acids, with oleic acid as the major component. A six-lump, nonisothermal kinetic model for the plug-flow reactor was developed to analyze palm oil cracking data. The model includes unconverted palm oil, gasoline fraction, kerosene fraction, diesel fraction, gaseous product, and coke. A nonselective catalyst deactivation function was incorporated in the model. The experimental cracking activity data obtained in the microreactor were used for the evaluation of kinetic parameters. The product yields predicted by the model showed a good agreement with the experimental data obtained in the microreactor as well as in the transport riser reactor. The model also accounts for the temperature drop due to endothermic cracking reaction as a function of residence time.