The Caterpillar micro mixer is an example of a simple, pilot-sized micro mixer-tube reactor that has an internal microstructure with a ramp-like shape inducing recirculation flow patterns, whereas the overall channel structure can be kept fairly large. The volume varies between 1 L/hr to several hundred liters per hour. Several hundreds of precision-engineered, star-shaped platelets can be stacked, and the flow can be distributed.

A PI reconfigurable reactor developed by the BHR Group (USA) has led to flexibility, a wide range of operating conditions, and easy construction (see Fig. 6.7). The reactor contains static mixer elements (see Fig. 6.8) packaged into a flexible "shell and tube" geometry, which gives a flexible design capable of operating over a wide range of conditions. Generally, static mixers are not flexible, but this design incorporates flexibility. It can be scaled up by adding more length.

Figure 6.7: Flexible reactor with static mixer elements (residence times 25 30 min, 20 bar, ?250 C, single-ended or double-ended design)

Figure 6.8: Micro-structured mixer elements

Production of glycidyl ethers by reaction between alcohol and chloroalkylepoxide in the presence of a catalyst is traditionally carried out in a batch reactor, and then the products are separated by distillation. The latter is also performed in batch mode (see Fig. 6.9). The reaction is highly exothermic, and the rate of raw material feeding is limited by the heat generated. The byproducts formed by side and consecutive reactions reduce the selectivity and increase the energy usage in the distillation columns. Using...