Simulation of deoxygenation of vegetable oils for diesel-like fuel production in continuous reactor

Abstract

A model for deoxygenation of vegetable oil components of renewable diesel manufacturing is proposed. The conversion of triglycerides over the deoxygenation catalyst in the presence of hydrogen were evaluated by including the rigorous kinetic data of complex reactions that happen in parallel and/or consecutively, including saturation, hydrogenation, hydrogenolysis, cracking, decarboxylation, decarbonylation, hydrodeoxygenation, methanation, and water-gas shift. A fixed-bed reactor was modeled using Aspen Plus® 8.8 software. The influence of reactor pressure, temperature, and H2/oil molar ratio was analyzed, in addition to type of feedstocks. The operational conditions in reactor considered optimized in this study for the deoxygenation of vegetable oils process were pressure 40 bar, temperature 300 °C, and H2/oil molar ratio of 2.5/1. For all oils analyzed, a conversion above 96% was observed, and the overall mass yields obtained from these in diesel-like hydrocarbons were > 78%. In addition, it was noted that the type and amount of hydrocarbon converted are mainly related to the initial composition of vegetable oil used as feedstock. Conclusively, the model proposed can be used for new product design, improving operation conditions, and help economic analysis in green diesel manufacturing.