Slits types

Right cut through the top part of the housing of the slit interdigital 3-D micro mixer comprising the slit-type focusing zone and the subsequent small channel to the outlet [40, 41). 

Mixer material Metal/stainless steel silicon /stainless steel glass Slit-type chamber 4.30 mm 500 pm initial width 150 pm 300 pm focused width depth 2.8 mm, 24 mm focusing length 126.7° expansion width expansion length expansion angle... 

Type of flow-through Rectangular chamber triangular slit-type Device outer dimen- 20 mm 16.5 mm sions diameter height... 

Reactor 19 [R 19] Slit-Type Interdigital Micro Mixer-Tube Reactor... 

One version of such a reactor concept is the combination of a slit-type in ter digital metal/steel micro mixer (for a detailed description see [R 18]) with a conventional tube. In [37], PTFE tubing was applied (Figure 4.20). 

Reactor type Slit-type interdigial micro mixer-tube Mixer material Stainless steel, nickel... 

Figure 4.20 Schematic of laboratory-scale reaction system with a slit-type interdigital micro mixer as central element, used at Merck site [134],...

OS 63] [R 27] [R 18] [P 46] Using a slit-type interdigital micro mixer prior to a liquid/liquid reaction system improves the conversion to 80%, hence close to the kinetic limits [117]. This is an improvement over using a microgrid in front of the reactor (see the Section Conversion/selectivity/yield - benchmarking to batch processing/kinetics, above). 

Mixer 42 [M 42] Interdigital Vertically Multi-laminating Micro Mixer with Slit-type Focusing - Plane Slit Mixer ... 

Mixer type Interdigital vertically multi-laminating micro mixer with slit-type focusing Number of micro channels 2 x 15... 

Slit-type chamber initial width, focused width, depth, focusing length, expansion width, expansion length, expansion angle 4.30 mm, 500 pm, 150 pm, 300 pm, 2.8 mm, 24 mm, 126.7° ... 

M 42] [P 39] In a slit-type interdigital micro mixer, first mufti-lamination patterns are created [20,124], Then, the multi-laminated stream is introduced into a chamber of larger cross-section. A jet is formed and induces two eddies in the dead zones adjacent to the initial channel (see Figure 1.97). Mixing is not completed within the chamber, as evidenced by the non-uniform color distribution. The contribution of the jet mixing to the total mixing is unclear. 

Slit-type filters have been fabricated to trap micrometer-sized particles and to retain suspension cells (e.g., blood cells). 

FIGURE 8.1 Filtrations of 5.78-pm-diameter latex beads by a slit-type filter. A 500-pm-wide and 5.7-Llm-dccp channel was fabricated on a 400-pm-thick Si wafer. The slit structure consisting of 5-pm-wide slits between 73-pm-wide posts was fabricated by DRIE [919]. Reprinted with permission from Elsevier Science. 

Retention of oligonucleotides immobilized beads was also achieved on a slit-type filter chamber fabricated on Si. The three different designs are shown in Figure 8.3 [829-831]. Although the flow rate decreased when the chamber was filled with beads, clogging of the filter was rare and reversible, especially with the design shown in Figure 8.3c [831]. 

The slit-type filter has also been used for cell retention. For instance, a porous filter has been used to retain rabbit blood cells in a whole blood sample. This filter was fabricated inside a glass microchannel using emulsion photopolymerization. The retained cells were then lysed for the assay of G-6-PDH [832],... 

A weir-type Si microfilter (3.5-pm gap), which was covered by glass, was fabricated to retain white blood cells (WBC) in whole blood. The cell-retention performance was better than with the slit-type filter (7-pm gap). Although the slit-type filter can retain non-deformable latex microbeads, deformable objects such as blood cells squeeze through the gaps [919],... 

A slit-type interdigital micromixer was used for fast mixing [30] and compared to a tubular reactor and five Kenics mixers connected in series. Details on further components of the micromixer rig were not given, but most likely a capillary reactor was added for efficient heat exchange. 

Process development was carried out at laboratory scale using a slit-type interdigital micromixer-reactor [31]. The whole flow guidance was provided by the micromixer and the outcoming solution was collected in a vessel. 

A slit-type interdigital micromixer has been used [34]. Details on the type of plant as well as on the processing were not given. 

An interdigital slit-type high-pressure micromixer followed by a tube (0.9 mm inner diameter 2.6 m long) was used [48]. The micromixer-tube reactor was submersed into a thermostat bath for temperature setting. HPLC pumps fed the monomer and initiator flows. A back-pressure cartridge (70 bar) and a pressure sensor served for pressure control. The temperature was set to 105 °C. The processing protocol was carried out conventionally, using the specs of similar batch processes. 

Handique K, Bums M (2001) Mathematical modeling of drop mixing in a slit-type micro-channel. J Micromech Microeng 11 548... 

Vq is the pore width for slit-type pores or the pore diameter for cylindrical pores. 

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