Thermodynamic Evaluation of the Lauric Acid Deoxygenation Reaction Using TeS Software

Brazil has strong potential to lead the global renewable fuels sector globally due to its vast biodiversity. Among its natural resources, babassu oil stands out due to high content of lauric acid. Hydrodeoxygenation (HDO) has emerged as a promising route for oilseeds conversion into hydrocarbons. This work aimed to perform a thermodynamic evaluation of lauric acid (model compound for babassu oil) deoxygenation, using the TeS (Thermodynamic Equilibrium Simulation) software to assess the n-dodecane and n-undecane production under varying operating conditions. Three conversion routes for hydrocarbon production were analyzed: hydrodeoxygenation (HDO), decarboxylation (DCOx) and decarbonylation (DCO). Simulations were conducted under temperature ranges of 473 – 673 K, pressures of 50 – 100 bar, and hydrogen to fatty acid molar ratios from 3.0 to 12.0. The results indicated that the HDO route is the most efficient for hydrocarbons production, as it promotes water formation as a byproduct without generating carbon oxides. As the hydrogen feed increases, larger amounts of water and unreacted hydrogen were observed in the products. Moreover, higher hydrogen feed compositions led to an increase in the production of dodecane and undecane. Temperature increase led to a reduction in lauric acid conversion, due to the exothermic nature of the HDO reaction. The most favourable conditions for conversion of lauric acid into n-dodecane were identified at 673 K, approximately 58 bar, and a hydrogen feed of 3 mol per mol of lauric acid. These results agree with literature. Additionally, the conditions for maximum CO and CO₂ formation, associated with the DCO and DCOx pathways, were identified at 673 K and 50 bar. Overall, the TeS software demonstrated strong versatility in simulating multiple chemical equilibrium reactions, providing a quantitative basis for predicting equilibrium compositions in chemical reaction processes and development of clean fuel technologies.