A lumped modelling framework for the epoxidation of vegetable oils and fatty acid methyl esters

Epoxidized vegetable oils and fatty acid methyl esters are promising bio-based alternatives to phthalates for plasticizer applications. Their synthesis typically involves the reaction of unsaturated double bonds with peracetic acid in a biphasic liquid–liquid system, where the simultaneous occurrence of reaction and phase partitioning makes process modelling particularly challenging. Existing models are often restricted to specific feedstocks and frequently rely on the simultaneous regression of kinetic and mass transfer parameters, thereby limiting their general applicability. In this work, a lumped modelling framework is developed to enable feedstock-independent simulation of the epoxidation of vegetable oils and biodiesel. The reacting mixture is represented as a pseudo-component characterized by its iodine number, which serves as a descriptor of the average degree of unsaturation, allowing different feedstocks to be described using a unified set of kinetic parameters. The model assumes kinetically controlled conditions, while liquid–liquid equilibrium is evaluated at each integration step using the UNIFAC method within a customized numerical scheme. The proposed approach reproduces experimental trends of conversion, selectivity, and oxirane oxygen content with accuracy comparable to literature models, while requiring a reduced number of adjustable parameters and avoiding the explicit estimation of mass transfer coefficients. The model is further applied to explore the effect of operating conditions and to identify optimal reaction regimes through systematic parametric analysis. Overall, the framework provides a computationally efficient and general tool for process screening, preliminary reactor design, and optimization of epoxidation processes aimed at the production of sustainable plasticizers