Ceramic Microreactors

Knitter, R., Liauw, M. A., Ceramic microreactors - fabrication and application, in Proceedings of the 27th International Exhibition-Congress on Chemical Engineering, Environmental Protection and Biotechnology, ACHEMA (19-24 May 2003), DECHEMA,... 

R. Knitter, M. A. liauwb. Ceramic microreactors for heterogeneously catalysed gas-phase reactions. Lab Chip 2004, 4, 378-383. 

A study of a ceramic reactor for on-site hydrogen production from propane at temperatures between 800 and 1000 °C was reported by Mitchell and Kenis [46]. They showed that the ceramic microreactor can be used with an S C ratio as low as 1.095 without coking or deactivation of the mthenium catalyst deposited on the SiC porous monoUths. 

Purchasable microreactors are limited in their temperature and pressure resistance, depending mainly on the reactor material used and the fabrication of the reactor. Most metallic microreactors operate at a maximum temperature of 500 °C, whereas ceramic microreactors offer temperature resistance up to 1100°C at ambient pressure and high chemical resistance. Metallic microreactors, in contrast, can withstand higher pressures generally. Further, it has to be considered whether the reactor material has any influence on the performance of the reaction, for instance unwanted catalytic activity. Normally most metallic microreactors can be provided in several materials. 

Depending on the material of the microreactor, different methods of catalyst deposition are feasible. Most of the mentioned techniques are possible for metallic microreactors especially sol-gel synthesis is very commonly used as a coating method. By the use of ceramic microreactors, several pretreatments such as anodic oxidation cannot be carried out in turn the deposition of carbon supports has been... 

J. Schiiret T. Baier, Hermetic gas-tight ceramic microreactors, Chem. Eng. Technol. 2005, 28, 465- 73. 

J. Hausselt,Microfabrication of ceramic microreactors, Microsyst. Technol. 2001, 7, 85-90. 

Ceramics offer advantages for the high temperature regime, as proven by the widespread use of ceramic monoliths. Interesting work has been performed by Wang et al. [637] on a ceramic microreactor made from ceramic tapes, which might be considered in the future for certain applications. 

Mitchell, M.M. and Kenis, P.J.A. (2006) Ceramic microreactors for on-site hydrogen production from high temperature steam reforming of propane. Lab Chip, 6. 1328-1337. 

A ceramic electrochemical microreactor for the methoxylation of methyl-2-furoate with direct mass spectrometry coupling. 

The development of microfabrication technologies for ceramic and metallic materials has significantly promoted, during the last decade, research in the field of microreactors, characterized by higher specific productivity, better control of operating conditions and a higher standard of intrinsic safety than large-scale reactors [33, 34]. 

Microemulsion is used as a special microreactor to limit the nano-sized particles growth. The shape of the microreactor depends on reaction conditions [9]. This method increases the homogeneity of the chemical composition at nano-level and facilitates the preparation of nano-particles with comparatively equal sizes [11]. The specific properties of the nano-particles make them suitable for microelectronics, ceramics, catalysis, medicine, cosmetics, as piezoelectric materials, conductors, etc. 

Figure 2.29 Photograph of the ceramic reactor housing and the quartz-glass tubulare microreactor (visible through the center hole) [59].

Giovannini, H., New process for manufacturing ceramic microfluidic devices for microreactor and bioanalytical applications, in Matlosz, M., Ehrfeld, W., Baselt, J. P. (Eds.), Microreaction Technology - IMRET 5 Proc. of the 5th International Conference on Microreaction Technology, Springer-Verlag, Berlin, 2001, 103-112. 

Battelle Pacific Northwest National Laboratories (PNNL, Richland, WA) are developing microreactors that produce synthesis gas. These reactors can be mass-produced to yield efficient, compact and cost-effective systems, and they have been made from copper, aluminum, stainless steel, high-temperature alloys, plastics and ceramics. Conventional technologies cannot take full advantage of the intrinsically rapid surface reactions involved in the catalytic conversion of hydrocarbon fuels, but microreactors with integrated catalyst structures can61. 

Fabrication of Microreactors Made from Metals and Ceramics... 

Although basic microreactors and arrays may be fabricated from either glass, polymers, metals or ceramics, advanced microreactors with multifunctional and reconfigurable capability will require construction from a set of diverse and integrated... 

Girault et at. developed a ceramic electrochemical microreactor (CEM) in which an array of platinum interdigitated band electrodes (gap between electrodes 500 pm) was screen printed on the ceramic surface (Scheme 4.39) [5 3], A methanolic solution... 

In the first two chapters, the fabrication of microreactors useful for chemical synthesis is described and opportunities as well as problems arising from the manufacture process for chemical synthesis are highlighted. Chapter 1 deals with the fabrication of metal- and ceramic-based microdevices, and Brandner describes different techniques for their fabrication. In Chapter 2, Frank highlights the... 

Methane decomposition experiments were conducted in a 5.0 ml fixed bed quartz microreactor using 0.3 g of catalysts. The catalysts were arranged within the reaction zone in several layers separated with ceramic wool to prevent clogging of the reactor due to produced carbon. The reactor temperature was maintained constant via a type K thermocouple and Love Controls microprocessor. The tubular reactor was made out of alumina and quartz tubings (I.D. 3-6 mm). 

The versatility of the crosslinked structures opens a new broad avenue for their application in several areas. As mentioned above, corona-crosslinked PFS assemblies demonstrate excellent shape retention upon pyrolysis and permit the formation of ceramic replicas. We have also recently shown that in a common good solvent, the PFS chains in the microgel interior of xPMVS can serve as a microreactor forthe localized production of metal nanoparticles [25], We are also about to begin light scattering studies of PMVS micelles, before and after corona crosslinking, and hope to use these experiments to learn more about the self-assembled structures formed in dilute solution. 

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