Reactor microstructured testing

Five different types of reactors, including tube reactors, static mixers and a microstructured reactor, were tested for the synthesis of an intermediate to 3deld a quinolone antibiotic drug, named Gemifloxacin (FACTIVE ) [13,14]. 

Figure 1.23 Large-scale reactor with microstructured internals tested at the industrial site of Degussa and developed jointly by a project team of several partners [137],...

For the chemical reactor, the researchers used a nanoparticle catalyst deposited on metallic micro-structured foils. They tested Cu/ZnO and Pd/ZnO catalysts deposited on the microstructured foils. The Cu/ZnO catalyst was more active than the Pd/ZnO catalyst and had a lower selectivity to undesired carbon monoxide. However, because the Pd/ZnO catalyst was more stable, it was selected for use in their fuel processor. The Pd/ZnO carbon monoxide selectivity of the powder catalyst pressed into a pellet was lower than that of the nanoparticle catalyst deposited on the microstructured foils. This effect was attributed to contact phases between the catalyst and the metal foils. ... 

Pfeifer, P., Schubert, K., Fichtner, M., Liauw, M. A., Emig, G., Methanol-steam reforming in microstructures difference between palladium and copper catalysts and testing of reactors for 200W fuel cell power, in Proceedings of the 6th International Conference on Microreaction Technology, IMRET 6 (11-14 March 2002), AIChE Pub. No. 164, New Orleans, 2002, 125-130. 

The first start-up of the plant was in June 2005 [67]. A temperature diagram shows that most of the heat is released in the retention time tube (see Figure 5.33). The temperature measured directly at the outlet of the microstructured mixer-reactor StarLam 3000 was below 50 °C even at higher throughputs. During the retention time, tube temperatures up to about 130 °C were reached. The throughputs for this first test mn were increased in three steps to up to 3600 kg/h. 

Aligned multiwall CNT arrays were synthesized as a basis for a microstructured catalyst, which was then tested in the Fischer-Tropsch reaction in a microchannel reactor [269]. Fabrication of such a structured catalyst first involved MOCVD of a thin but dense A1203 film on a FeCrAlY foam to enhance the adhesion between the catalyst and the metal substrate. Then, multiwall CNTs were deposited uniformly on the substrate by controlled catalytic decomposition of ethene. Coating the outer surfaces of the nanotube bundles with an active catalyst layer results in a unique hierarchical structure with small interstitial spaces between the carbon bundles. The microstructured catalyst was characterized by the excellent thermal conductivity inherent to CNTs, and heat could be efficiently removed from the catalytically active sites during the exothermic Fischer-Tropsch synthesis. 

K. Schubert, W. Bier, J. Brandner, M. Fichtner, C. Franz, G. Linder, Realization and testing of microstructure reactors, micro heat exchangers and micromixers for industrial application in chemical engineering, in W. Ehrfeld, I.H. Rinard, R.S. Wegeng (Eds.), Proceedings of 2nd International Conference on Microreaction Technology (IMRET 2), AIChE, New Orleans, 1998, p. 88. 

O. Schwarz, B. Frank, C. Hess, R. Schomacker, Characterisation and catalytic testing of VOx/A1203 catalysts for microstructured reactors, Catal. Commun. 9 (2008) 229. 

The most convincing tests of the new tool microstructured reactor and new type of processing, named chemical micro process engineering, are real-life applications. Some new examples are given below, either with IMM involved as research entity or with IMM tools being used. The next subsection gives the first examples of industrial case studies for chemical production, either with IMM or other suppliers tools. There are certainly more such examples, some of which are known to the authors however, these have to remain confidential at present, although some may be made public in the near future. Several subsequent subsections present IMM in-house process developments that were made to be launched to clients. 

In contrast to aqueous corrosion typically involving loss of electrons from the dissolving metal, liquid metal corrosion is generally considered to proceed by simple solution mechanisms. The principal variables affecting corrosion in a liquid metal system are temperature or temperature range or cycling, elements present, area-to-volume ratio, purity, flow velocity, surface condition, and microstructure. In reactor applications, the neutron flux may be an additional factor. In combination, these variables produce enough complexity so that in the present state of the art, it is rarely possible to make confident predictions about the performance of a previously untried systan. Empirical tests are usually required. 

It is widely known that radiation embrittlement behaviour of reactor pressure vessel (RPV) steels depends on various parameters such as material composition, neutron flux and irradiation temperature. Sound understanding and modelling of embrittlement mechanisms require systematic knowledge of effects of individual parameters and their synthesis on microstructural development and then mechanical properties. Most such knowledge has been obtained from single-parameter experiments using test reactor irradiation. This is because test reactor irradiation allows researchers to obtain mechanical property data together with microstructural data on materials with well-controlled chemical compositions under well-controlled irradiation conditions such as flux and temperature. Surveillance data in commercial power reactors are non-systematic in this context and relevant microstructural data are very scarce. 

Fukuya K, Ohno K, Nakata H, Hyde J M and Dumbill S (2003), Microstructural evolution in medium copper low alloy steels irradiated in a pressurized water reactor and a material test reactor , J Nucl Mater, 312,163-173. 

In the development of a new correlation method, microstructural characterization of the surveillance materials of some PWR plants was also performed in order to understand the embrittlement mechanism of RPV steels with different Cu contents. At the same time, another test reactor irradiation project, the PLIM project, was also conducted by Japan Nuclear Energy Safety (JNES), where extensive microstructural characterization of base metals and weld metals with a wide range of chemical compositions in terms of Cu and Ni was performed using APT, transmission electron microscopy and positron annihilation to obtain new insights with the embrittlement mechanism at high fluences.The mechanism of embrittlement identified or confirmed in these projects was summarized as follows ... 

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