(689d) Production of Green Diesel by Hydrocracking of Canola Oil on Ni-Mo/γ- Al2O3 and Pt-Zeolite Based Catalysts

As an alternative way to produce biodiesel, the hydrocracking of canola oil was studied on different types of catalysts. Experiments were carried out in a batch reactor over a temperature range of 280 to 380°C, initial hydrogen pressure of 4 to 9 MPa, and reaction times from 1 to 6 hours. Three types of bifunctional catalysts were synthesized and used: Pt/USY zeolite, Pt/H-ZSM-5 and sulfided NiMo/γ- Al₂O₃. At the studied conditions, the hydrocracking on Ni-Mo/γ- Al₂O₃ catalyst gave the highest conversion to liquid hydrocarbons. The Pt-zeolite catalysts revealed a strong catalytic activity for both cracking and hydrogenation reactions and therefore, in order to achieve a relatively high conversion, the initial hydrogen pressures were required to be higher than those with NiMo/γ- Al₂O₃. The time of reaction was limited in observance of the rates of reaction for both hydrogenation and cracking reactions, which strongly depended on the type of catalyst. In most cases, the GC analysis of the gaseous phase revealed the presence of mainly CO₂, CO, propane, and remaining hydrogen. Oxygen was not present. The hydrocracking of canola oil on all three catalysts produced a diesel mainly composed of normal paraffins from C₁₅ to C₁₈. Traces of unconverted fatty acids were also detected. After evaluation of the composition and physical properties of the liquid product, they were found to be very similar to those of petro diesel, but with the advantage that the former contains a higher weight percentage of C₁₇ and C₁₈ hydrocarbons, and therefore a higher cetane number. The effects of operating conditions and catalyst type will be presented in detail.