Microreactors applications

Taghavi-Moghadam, S., Golbig, K., Microreactors application of CYTOS -technology from laboratory to production scale, MST News 3 (2002) 36-38. 

Pennemann H, Watts P, Haswell SJ, Hessel V, Lowe H (2004) Benchmarking of microreactor applications. Qrg Process Res Dev 8 422-439... 

In microreactor applications, the segmented flow pattern (Figure 1.3) is most common. Here, discrete droplets behave as separate reactor vessels that are con-vected along in the microfluidic network by the continuous carrier liquid. Similarly, the longitudinal dispersion of the continuous phase can be suppressed by the use of discrete droplets or bubbles of the segmenting phase. 

A simple case that can be solved analytically is the so-called Graetz problem, in which mass transfer to the wall of a straight channel is calculated for the entry region of a microchannel where an infinitely fast reaction occurs at the wall. This problem, depicted in Figure 11.1, is representative for many aspects of laminar-flow mass transfer in microfluidic systems and heterogeneous microreactor applications, so we discuss it in some detail. 

In many multiphase microreactor applications, stable fluid interfaces have been particularly important for performing gas-liquid reactions in the annular flow... 

Ozone is a god target reagent for microreactor applications since it is toxic, difficult to handle and very reactive. A silicon-etched 16-channel (600 (tm x 300 pm x 22.7 mm) microreactor covered with Plexiglas was used for oxidation of 1-decene into nonanal with quantitative conversion and selectivity [20]. This reaction proceeds in fact through the formation of the very reactive intermediate ozonide, which formally results from [3 + 2] addition of O3 to the C=C bond. A consecutive reduction step with P(OEt)3-EtOAc is required to yield the aldehyde. The reaction time is as short as 0.32 s. From the published data, a daily production of ca. 1600 g of nonanal per day may be obtained, which is well suited for preparation in fine chemistry. 

The topic of this chapter is challenging in two ways. The first issue is the term consumer goods , which can be used broadly and maybe raises different expectations to this chapter. The second issue is the low level of information available about microreactor applications in the consumer goods industry. 

General Aspects of Microreactor Applications for Emulsification Processes... 

Some additional and more specific aspects of microreactor applications for emulsification are addressed in the following sections. 

As stated above, the focus of recent investigations of microreactor applications in the field of emulsification was on the use of micromixers, and different types of micromixers have been employed. However, it is difficult to compare them with regard to liquid-liquid dispersion performance since the mixers are most often investigated for different specific applications. However, a suitable comparison is the basis for future targeted equipment selection. Furthermore, micrombcers are in competition with conventional and other innovative equipment such as static mixers, membranes and homogenizers. Therefore, benchmarking with such equipment is also required. 

Outline of Additional and Potential Aspects of Microreactor Applications in the Consumer Coods Industry... 

Outline of Additional and Potential Aspect of Microreactor Applications I 393... 

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