Microfluidic Reactor Types

Inquire about the microfluidic reactor technology used for a complex reaction scheme, the reasons for choosing that particular reactor type, and the prospects of adopting a new design. 

Two types of bioreactors are commonly used in industry for performing enzyme-catalyzed transformations the stirred tank reactor and the packed or fluidized bed reactor [28]. Substitution of these weU-established reactors by a system based on microfluidic technology wiU happen only if there are clear and compelling advantages in so doing. It is therefore necessary to consider, in a rigorous and... 

The characteristic features of microsystems stem from the small size of the space in the microstructures. Therefore, microsystems are not necessarily small systems in total size. They can be large in total size as long as they contain microstructures that can be used for chemical reactions. This sharply contrasts with the concept of a lab-on-a-chip, which should be small in total size. It is also important to note that microsystems are normally set up as flow-type reactors with a constant flow of solutions through a microstructured reaction chamber or channel. Although the reactor s capacity at any one time is small, total production capacity over time is much greater than may be imagined. Therefore, microflow systems are not necessarily used solely to produce small quantities of chemical substances. In fact, a microfluidic device has been developed that fits in the palm of the hand but can produce several tons of a product per year (see Chapter 10). 

MicroChannel Enzyme Reactor. Enzymatic conversion is receiving attention because it is an environmentally friendly approach to synthesizing chemicals. Reactions can be carried out enzymatically in the solution phase or by immobilizing enzymes on microfluidic walls. The use of the latter type of reaction has the same mass and heat transfer advantages as the use of a microfluidic synthetic reactor. More information can be found in a published review article [6] and in the article microfluidic bioreactors in this encyclopedia. 

Elimination is one of the most important types of reactions for making carbon-carbon multiple bonds in organic synthesis. However, only a few examples of elimination reactions in microflow reactors have been reported. P-Hydroxyketones provide the corresponding dehydrated products, a,P-unsaturated ketones, in almost quantitative yields under the microfluidic conditions, whereas conventional macro batch reactors give lower yields of the products due to recovery of the starting materials and formation of other hydrophobic byproducts (Figure 5.3) [21]. 

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