Simulation of the oxidation of microencapsulated oil based on oxygen distribution – Model setup and validation

Abstract

Autoxidation of microencapsulated oil requires that atmospheric O 2 is in contact with the encapsulated oil. A diffusion based simulation coupled with reaction kinetics is proposed, which allows to study the effect of physical powder properties on the oxygen distribution and oxidation. The effective hydroperoxide formation rate was linked to the oxygen concentration by storing fish oil distributed on powder under atmospheres with varied O 2 levels. The model geometry was generated based on particle diameter, oil load and oil droplet size distribution. The oxygen distribution profile and the hydroperoxide concentration were calculated up to 100 days of storage for two scenarios, namely considering and neglecting the lag phase. Simulation in 2D and 3D resulted in the same trend, even though the hydroperoxide concentration was higher when considering the third dimension. For real encapsulates with different powder diameter, simulated data were in good agreement with experimental results. • The hydroperoxide formation rate was depended on the oxygen level in the atmosphere. • Simulation visualizes the O 2 and hydroperoxide distribution profile in encapsulates. • 3D simulation leads to more hydroperoxides, but in a same trend as calculated in 2D. • For real encapsulates simulated data are in good agreement with experimental result.