Silicone microreactor

ScHWESiNGER, N., Marufke, O., Qiao, F., Devant, R., Wurziger, H., A full wafer silicon microreactor for combinatorial chemistry, in Ehrfeld, W., Rinard,... 

Figure 6. Silicon microreactor for preferential oxidation of CO designed for a 0.25 We fuel cell. (The researchers wish to express their gratitude to DARPA for funding Grant N66001-02-1-8942.)...

Rangelow IW, Kassing R. Silicon microreactors made by reactive ion etching. Proceedings of the 1st International Conference on Microreaction Technology. Berlin Springer, 1998 169-174. 

Loebbecke, C. S., Schweikert, W., Tuercke, T., Antes, J., Marioth, E., Krause, H., Applications of FTIR microscopy for process monitoring in silicon microreactors, in Proceedings of the VDE World Microtechnologies Congress, MICRO.tec 2000 (25-27 Sept. 2000),... 

For enzyme attachment to the silicon microreactor tested, a layer-by-layer technique was employed to build a multilayer system of polyions and enzyme. Deposition of multilayers was accomplished by alternating positively and negatively charged layers of polydimethyldiallyl ammonium chloride (PDDA) and polystyrene sulfonate (PSS), respectively, to which was attached urease enzyme. After depositing in succession three layers of PDDA, PSS, and PDDA, three layers of urease enzyme were alternately deposited with three layers of PDDA. The resulting architecture is described as follows ... 

Srinivas, S., Dhingra, A., Im, H., and Gulari, E. A scalable silicon microreactor for preferential CO oxidation Performance comparison with a tubular packed-bed microreactor. Applied Catalysis. 

M. Roumanie, C. Delattre, F. Mittler, G. Marchand, V. Meille, C. de Bellefon, C. Pijolat, G. Tournier, P. Pouteau, Enhancing surface activity in silicon microreactors Use of black silicon and alumina as catalyst supports for chemical and biological applications, Chem. Eng. J. 135 (2008) S317. 

Kuhn, S., Hartman, R. L., Sultana, M., Nagy, K. D., Marre, S., Jensen, K. F. (2011). Teflon-Coated silicon microreactors Impact on segmented liquid—liquid multiphase flows. Langmuir, 27, 6519-6527. 

Silicon-Based Microreactor Systems Silicon is one of the most common materials that have been used for various MEMS devices. Silicon has a high elastic modulus (130-180 GPa) with small thermal expansion and low intrinsic mechanical loss and relatively good chemical compatibility [7]. The surface of the silicon can be easily modified by oxidation to form an oxidized silicon microreactor which is functionally... 

The presence of high heat transfer rates is another effect which is also attributed to the high surface-to-volume ratio. Heat transfer coefficients up to 41,000 W/m K have been reported in silicon microreactors, as compared with 2,500 W/m K in conventional-scale reactors. In the case of low-thermal-mass microsystems, convective heat loss to the environment can be much more significant in microreactors than in conventional systems owing to their high surface-to-volume... 

Ke C, Kelleher AM, Bemey H, Sheehan M, Mathewson A (2007) Single step cell lysis/PCR detection of Escherichia coli in an independently controllable silicon microreactor. Sens Actuators B 120 538-544... 

Flogel et al. [97] described a silicon microreactor (the same as in Figure 1.11) for peptide synthesis, which also allows a quick screening of reaction conditions. Using peptide couplings with Boc- and Fmoc-protected amino acids, significant amounts of peptides could be made in 1-5 min at temperatures as high as 120 °C. Synthesis efficiency was further enhanced by the use of a fiuorous benzyl tag for the assembly of P peptides this method is particularly useful for the purification of poorly soluble products. 

Jensen and coworkers employed a silicon microreactor (Figure 11.7) to perform aminocarbonylation reactions of aryl halides with morpholine [13]. The results show that carbonylation selectivity (mono- versus double carbonylation) depended on the reaction temperatures and CO pressures (Table 11.3). They also demonstrated that high-throughput screening of the optimal reaction conditions (temperature and pressure) could be performed with their system. 

In the field of microreactors, two main configurations exist, one being the direct coupling of the outlet of a single microreactor to a GC-MS system, such as via a capillary, which is made compatible with the flow requirements of the GC-MS system. An example of this concept can be found in the work of Besser and coworkers, who applied on-line GC-MS for kinetic studies of the preferential oxidation of CO in silicon microreactors the microchaimel walls of which were covered with a thin-film catalyst [50]. The outlets of four silicon microreactors running in parallel are fed... 

A silicon microreactor for preferential oxidation was designed by Srinivas et al. [163], which was 6 cm x 6 cm wide and long, while the flow path was only 400 pm high. Instead of microchannels, pillars were chosen for the flow distribution in the reactor. The reactor was coated with 2 wt.% platinum/alumina catalyst with a thickness of 10 pm. Tests were performed at an O/CO ratio of 2.0 and a high VHSV of 120 l/(h gcat)- Not more than 90% conversion of carbon monoxide could be achieved in the reactor at 210°C reaction temperature, while similar results were obtained for a small fixed catalyst bed. 

Thin layers of catalyst can be deposited onto the surface of silicon microchannels by physical vapour deposition. Silicon is the preferred material, because the equipment for physical vapour deposition is available at microelectronics fabrication sites, which can also produce silicon microreactors. Physical vapour deposition such as cathodic sputtering, electron beam evaporation and pulsed laser deposition but also chemical vapour deposition create uniform metal surfaces with thicknesses in the nm range. Such coatings are rarely suitable as catalysts. However, a few exceptions such as hydrogen oxidation [145] and reactions in the very high temperature range do exist. 

Roumanie et al. tested catalysts in a chip-like silicon microreactor for methylcy-dohexane dehydrogenation [280]. A platinum/alumina catalyst achieved 88.5% conversion, while a platinum film sputtered onto black silicon showed only 2% conversion. Low activity is frequently observed for non-dispersed noble metal surfaces. 

Figure 7.41 CFD simulation of the flow profile in the silicon microreactor developed by Srinivas et al. [551] left, fluid inlet region right, interior region.

Synthesis of another /3-peptide was also performed. See-berger et al. performed the synthesis of oligo /3-amino acid using amino acid fluoride in a silicon microreactor [2]. They developed a method for high-efficiency synthesis that is capable of large-scale production. 

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