Production of Biodiesel from Palm Oil by Extractive Reaction

Process integration looks for the integration of all operations involved in the production of one specific product. This can be achieved through the development of integrated processes that combine different steps into one single unit. The reactive extraction is an integrated process simultaneously combining the chemical reaction and liquid-liquid extraction. The latter phenomenon allows the continuous removal of the reaction products favoring the direct conversion in the case of reversible reactions like the esterification of vegetable oils with methanol. The objective of this work is to evaluate the possibility of applying the integration principle to the biodiesel production by extractive reaction from palm oil. During the esterification of palm oil with methanol, the products formed (methyl esters and glycerin) generate two liquid immiscible phases. This fact makes possible the separate removal of two product streams: biodieselenriched (extract) and glycerin-enriched (raffinate) streams. In order to accomplish the assessment of the proposed simultaneous integrated process, the thermodynamic analysis of the liquid-liquid phase equilibrium was carried out based on the principles of the topological thermodynamics. Thus, the study of the interaction between the chemical transformation and the liquid equilibrium allowed determining that an extractive reaction process for biodiesel production is possible. Then, the set of operating conditions for the process was defined. Whit this information, the analysis of the integrated process was performed by using a process simulator. The outcomes obtained were compared to the conventional process where the reaction and the extraction are accomplished separately. The proposed methodology allowed clearly elucidating if an extractive-reaction process can be implemented. This analysis method makes possible the improvement of the rigorous simulation by delimiting the space of operating conditions and, consequently, achieving savings in the costly experimental runs. In this way, the energetic and economic advantages of the extractive reaction process for biodiesel production from palm oil are demonstrated.