ISBN 9783843918305

978-3-8439-1830-5, Reihe Verfahrenstechnik

Alexander Niesbach
Design of Reactive Distillation Processes Using Bio-based Raw Materials

261 Seiten, Dissertation Technische Universität Dortmund (2014), Softcover, A5

Zusammenfassung / Abstract

Due to the scarcity of fossil raw materials, the development of processes using bio-based resources is currently explored. The two main challenges of using bio-based feedstocks are the economics and the complexity of the impurity profiles. To account for these issues, design approaches are needed for the production of bio-based chemicals to allow an integrated design of upstream and downstream processes. By the help of these approaches, critical impurities affecting the downstream processing can be identified. Hence, this thesis presents an integrated design approach for using bio-based feedstocks for reactive distillation processes.

The developed approach is used to identify the impurities that should be avoided or reduced in the upstream processing or the purification of the reactants to allow a production of a biochemical product with the desired quality. The criteria for the impurity identification are based on the used reaction and separation technologies. The design approach covers the development of new processes using biochemical feedstocks and the alteration from conventional to bio-based feedstocks for existing processes, the two possible areas of application for biochemicals. To achieve reliable results for the presented design approach, detailed models and experimental data for the model validation are crucial. Therefore, experimental results of a pilot-scale reactive distillation column are used to validate a nonequilibrium-stage model. The validated model is used for an economic optimisation of the process. Based on thermodynamic and physical property data analysis and reactive distillation process simulations of the optimised column design, critical impurities are identified among all possible bio-based impurities. Subsequently, a process analysis is performed to determine an operating window of the reactive distillation process that still allows a production with the desired specification for the product. Furthermore, possible process alterations are studied.

The developed approach is applied to two different case-studies: the synthesis of bio-butyl acrylate for the polymer industry and the production of bio-butyl butyrate for the flavour industry.