Modelling Gas and Gasoline Production from Cottonseed Oil on Fixed-fluidized Bed Catalytic Cracking over Nbfeapso-5 Molecular Sieve

The potential for producing hydrocarbons from the conversion of biofuels has been the focus of attention in recent years. In a preliminary study, we observed that it was possible to produce biofuels from cottonseed oil by fixed-fluidized bed catalytic cracking at ambient pressure, using fluid catalytic cracker equilibrium catalyst. In the present work, the production of biofuels from cottonseed oil by fixed-fluidized bed catalytic cracking at ambient pressure, using niobium containing aluminophosphate molecular sieve (NbFeAPSO-5), was studied. The effect of reaction temperature (400-500°C), catalyst-to-oil ratio (6-10) and residence time (50-90 s) were studied. The response surface methodology was used to determine the optimum values of the operating variables for maximum yield of biofuels in the liquid product obtained. The optimum values of reaction temperature of 420.2°C, catalyst to oil ratio of 8.8 g/g and the residence time of 51 seconds were obtained for maximum yield of light fuel oil (≤ 360°C) 68.6 wt%, gasoline fraction (≤ 205°C) 37.7 wt% and minimum yield of gas 15.6 wt%. The catalytic cracking of cottonseed oil in a fixed-fluidized bed reactor produced a liquid product rich in gasoline and diesel fraction.