ISBN 9783843930178

978-3-8439-3017-8, Reihe Technische Chemie

Björn Dreisewerd
A Contribution to Simulation-Based Process Design of Phytoextractions

164 Seiten, Dissertation Technische Universität Dortmund (2016), Softcover, A5

Zusammenfassung / Abstract

Phytochemicals are important substances for pharmaceutical, food and cosmetics industry. One operation to recover the target components from the plant material is the phytoextraction. Though the principle is long known, the mass transfer phenomena are still not fully understood, leading to a high experimental effort for process design. Therefore, systematic design strategies assisted by reliable process simulations are needed to reduce the experiments for designing phytoextractions.

In this thesis, the utilization of models with different approaches, i.e. kinetic models and those based on the quasi-equilibrium, for simulation-based process design is investigated. They are analyzed regarding, e.g. their representation of experimental data and their prediction of the extraction behavior at operating conditions not experimentally determined. Furthermore, an experimental procedure for the determination of the solute-solid interactions is proposed and validated. This is of high importance, since these are a parameter in many models, but no reliable method for their determination has been proposed, yet.

The investigations showed the potential to reduce the experiments using kinetic models was limited. The kinetics was influenced by system-specific effects which were not considered in any model investigated. Considering the investigation on the quasi-equilibrium model, the model was able to predict multistage leaching experiments by performing single-stage extractions only. Additionally, a simulation-based process design study revealed the simulation of multistage extractions and the variation of the liquid to solid ratio were always important for process design, while optimizing the time of extraction via a kinetic model was needed in certain cases only. Based on these findings, a design strategy for phytoextraction processes was proposed. In there, experiments for parameter determination are defined, allowing to identify the operating parameter with the most significant impact on specific costs. Only in case the time of extraction has a crucial influence on the specific production costs, the more complex kinetic modeling approach is chosen and a more detailed experimental analysis of the kinetics is proposed. Therefore, the experiments can be adapted to the requirements of a process design task given.