Design of a biodiesel production plant : a catalytic process using ordered mesoporous alumina supported catalysts

Abstract

Alternative energy demands are growing, and biodiesel is a promising potential to replace fossil fuels. This potential is of important interest due to the fact that biodiesel is a eco-friendly and renewable source of energy. This work presents the utilization of a basic heterogenous catalyst for the production of biodiesel through the transesterification reaction of refined sunflower vegetable oil. Prepared KOH/Al2O3 catalyst was implemented to reach high biodiesel yields. This catalyst was prepared via wetness impregnation and incipient wetness methods to study the effect of preparation techniques. This novel catalyst was prepared via different KOH loadings (10 wt. %, 20 wt. %, and 30 wt. %) and tested for transesterification reaction via different CTORs (2.5 wt. %, 5 wt. %, 7.5 wt. %, and 10 wt. %). The reaction was conducted in batch reactor at 60 °C. A yield of 99% was obtained using 30 wt. % loading KOH supported on Al2O3 within 15 minutes. The reusability of the catalyst was studied for a reaction time of 4 hours and proved a high stability for 3 consecutive runs. Eggshells and KOH impregnated on eggshells were prepared and tested for biodiesel production. Relatively low biodiesel yields were obtained for both catalysts limiting their use for transesterification reaction. Moreover, a scaled-up process design for a biodiesel plant in Zahleh was investigated using the prepared KOH/Al2O3 catalyst. This process requires the collection of waste vegetable oil from households and industries, the pretreatment of this oil, the transesterification reaction, and the purification of the produced biodiesel. A PBR was used for this process along with an eggshells designed membrane for the purification of biodiesel for further applications and uses. An environmental and economic assessments were studied to ensure a high efficiency operation within allowable costs.