Parallel microreactor

High-throughput testing was accomplished using a system of 16 continuous fixed-bed parallel microreactors, able to work up to 80 bar. The principal characteristics of this reactor are summarized as ... 

In 2004 Clariant set up a new centre for the development of microreactor technology in Frankfurt, Germany, called the Clariant Competence Center for Micro Reaction Technology. Its facilities include two microreactor pilot plants and a dedicated laboratory. Clariant says that by using parallel microreactor modules makes it possible to turn out kilogram or even ton quantities of a product [B-46],... 

Novel parallel microreactor systems for fermentation are demonstrated in a new program initiative in the DuPont/MlT alliance... 

Full factorial designs with M levels can be used for estimating polynomials of order at most M -1. Naturally, these designs are feasible only with very few variables, say maximum 3, and typically for only few levels, say at most 4. For example, a 44 design would contain 256 which would be seldom feasible. However, the recent development in parallel microreactor systems having e.g. 64 simultaneously operating reactors at different conditions can make such designs reasonable. 

The effect of calcination versus reduction. In this case, catalyst activities were first obtained using the 10-port parallel microreactor to determine the main effects of particle size and pretreatment for several samples in a single run. Then, detailed kinetic information was obtained in the recycle microreactor. Because the activity was measured under oxidizing conditions, we were not sure if, under reaction conditions, the surface was oxidized or reduced, so this question was addressed first. To stabilize the state of the surface and to ascertain the role of the oxidized versus the reduced surface, prior to each run, the catalysts were pretreated either in air or... 

S, Nelson, S, G, Weber, Capillary-based, serial-loading, parallel microreactor for catalyst screening. Anal. Chem. 2006, 78, 1972-1979,... 

Figure 1.8 Parallel microreactor system (the so-called CYTOS Pilot System) designed and commissioned by CPC for Clariant in 2001, for the manufacturing of diazo pigments. Source Reprinted from Ref [50], Copyright (2007), with permission from Elsevier.

There are no scaling-up problems with microreactor systems. The production capacity can be increased simply by increasing the number of microreactor units used in parallel. 

Figure 7.12 Conceptual sketches of two types of microreactor-heat exchanger (a) parallel flow and (b) cross flow.

Catalysts pre-treatment (calcination and reduction) was performed in the same testing system or in a parallel automatic activation system prior to reaction test Calcination is carried out at 600 °C under airflow for 8 h and reduction at 250 °C for 2 h under hydrogen flow. Catalytic tests were carried out at 30 bar total pressure, temperature range 200-240°C, and 2.26h-1 WHSV, H2/hydrocarbons molar ratio of 2.93. Each fixed bed microreactor contained 500 mg of catalyst (particle size 0.4—0.6 mm, for which there are no internal diffusion limitations). Reaction products distribution are analysed using a gas chromatograph (Varian 3380GC) equipped with a Plot Alumina capillary column. 

Figure 2 Microreactor for parallel screening of catalysts for partial oxidation of methane. (Source D. Honicke, TU Chemnitz.)... 

Microreactors for multiple parallel reactions, either fast or long Semi-batch systems similar to titer-plates connected to microdispensing systems and separation/analysis units... 

If microreactors, either as components or integrated systems, will run in parallel as an array, new solutions for feeding or dispensing systems have to be developed. This is also true for the process control of a large number of product streams which will be a challenge for realization. Tomorrow s answers to these questions will determine which type of microreactor will be favored and will specify the major applications, either simulation of processes, synthetic production or mass screening. 

A second field of application may be in the on-site and on-demand production [3,8,25]. A number of chemicals, especially those which are explosive or toxic, can not be efficiently produced at present on a medium or small scale, although large-scale processes exist. A parallelization of several microreactor units could synthesize flexible amounts of chemicals and may even allow a transport of the reaction units if desired. 

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