(46f) Multiple Purpose Micro Reaction Plants for Development and Production

Since more than 15 years micro reactors have been developed. It turned out that Micro Reaction Technology (MRT) is a perfect tool for Process Intensification (PI), to characterize chemical reactions (kinetics, thermodynamics), to develop new chemical reactions and optimize conventional reactions, and to produce in a sustainable way: safer and with less reagents, less waste, less energy consumption. Even though these advantages are accepted by scientists, the technology is still not used broadly in the chemical industry. The following talk will explain a new concept of a modular micro chemical plant to use these advantages. This new concept facilitates the multi-purpose use of a micro reaction plant and shows the economical benefits. The described plants have been designed and built to carry out different chemical reactions (gas-liquid or liquid-liquid, at low or higher temperatures, at different pressures, at different flows, one or more step reactions, etc.). For this, the plant consists out of a "base plate" and different "reaction plates". The "base plate" includes all necessary "peripheric" equipment, like pumps, mass flow controllers, sensors, filters, temperature control circuits, electronic control unit, etc. The electronic hardware for controlling is directly combined with these components to facilitate any changes. With these functions the "reaction plates" can be used easily. They include the reactors, sensors and components, which are specific for a given reaction. By connecting the "reaction plate" to the "base plate", the electronic control unit automatically realizes which pumps, sensors and feeding lines are required and starts the required software. With this set-up it is very simple to change from one reaction to another within minutes, run a cleaning cycle for several minutes and start the new reaction. (Fig 1 and 2) Besides changing modules, it is also important to vary parameters within one set-up. For this purpose different tools are implemented: - The electronic control unit allows to program a combination of different experiments with different flow, temperatures, and pressures. - To vary independently flow and residence time, an adjustable residence time module has been developed which allows to use residence times between 1s and several hours. - An autosampler can be integrated to collect product fractions, produced under different conditions. - IR-measurements or pH- and viscosity sensors can be integrated to have an online-analysis of the chemical reactions. After development of a certain reaction, it is possible to use the same plant for production up to several kg per day. With small changes (larger pump head, larger reaction device) or a parallelization of up to 10 reactors, it is possible to achieve up to 1 ton per day (depending on the chemistry). When increasing the production volume, safety might become an issue. Even though micro reactors are very "safe" (low internal volume !) different safety feature have been included in the multi-purpose plants: pressure relief valve, check valves, leakage sensors, software controlled limits for temperature and pressure, etc. Examples will be shown. The micro fluidic devices used in this work are made out of glass, because of its ideal properties, like chemical stability or optical transparency. For the same reason, all modules to run a glass micro reactor, e.g. pumps, valves, tubings, temperature-, pressure-sensors, analytical modules, and safety installations use materials with the same chemical stability. In a conventional chemical production the apparatus is fixed and built out of standard equipment. The chemistry is forced to work in this reactor. In contrast, micro reactors give the opportunity to build a fluidic system which is optimized for the chemical reaction ! Therefore, a flexible material and structurisation process is needed. At mikroglas mainly the photo etchable glass FOTURAN is used. With this material micro reactors, mixers, heat exchangers, dwell devices, and analytical modules have been built. Even very complicated three-dimensional structures can be manufactured by etching different geometries into different layers and bond up to 20 of these layers together to form a micro reactor. Other materials (like stainless steel or titanium) can also be used if required, e.g. for higher pressure. Different examples will be shown during the presentation which show the advantages of the applied technology, e.g. two-phase systems, catalytic reactions, polymerizations, photo reactions, ozonizations, hydrobrominations, etc. The authors like to thank the German Ministry for Education and Research for funding parts of this work and the partners within the project ZOHIR (Bayer Schering Pharma AG, Leibniz-Institute for Catalysis, infrared fiber sensors) for their extensive help. Fig.1 Micro reaction equipment for multipurpose use Fig.2 Flow diagram for a fluorination reaction (screen shot of the SIMATIC control unit)