Toray Hi-mixer

In a detailed process optimization study, the impact of the type of micromixers and process parameters was determined [56]. As a result, a pilot with a Toray Hi-mixer connected to a shell and tube microheat exchanger was constructed. Continuous operation for 24 h was carried out to obtain pentafluorobenzene (PFB) after protonation (92% yield). In this time, 14.7 kg of the product was produced, that is, about 5 t/a. Thus, the industrial-scale production carried out using a batch reactor (10 m3) can be replaced by adding only four microflow systems of the scale investigated. The pilot plant produces 0.5 kg in 6h continuous operation, thus about 730kg/a (see Figure 5.19). The name of the industrial company was not disclosed. 

The Toray Hi-mixer is a special type of manifold split-and-recombination micromixer. The structure of the Hi-mixer is shown Figure 7.12. In the Hi-mixer, when two layers of the solutions enter the mixing element, they are split into eight layers by using twist walls in the element. Therefore, in this method, the number of layers increases exponentially by repeating the operation (4" after the wth iteration). 

Figure 7.12 (a) Structure and (b) photograph of the Toray Hi-mixer. Copyright 2005... 

A microflow system for relatively large-scale production (i.e., a pilot plant) composed of a Toray Hi-mixer connected to a shell and tube microheat exchanger has been constructed (Figures 10.8 and 10.9). The... 

Figure 3.9 shows the structure of a Toray Hi-mixer, [5] which is one example of such a split- and recombination-type micromixer. This mixer divides the solution into four at a time, and thus, the two layers introduced initially are split into eight layers at the first element and then into 32 layers at the second element, making the diffusion distance short very quickly. 

Fig. 3.9 Mixing in a Toray Hi-mixer (a manifold split and recombination-type micromixer)...

Another mixer that incorporates the twisted tape feature is the Hi-mixer from the Japanese company Toray. The elements consist of a cylinder with two circular channels and a cone-shaped entrance and exit. Within the circular channels is the twisted tape, twisted over 180° see Fig. 7.144. 

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