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Microreactor
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Microreactor
A microreactor or microstructured reactor or microchannel reactor is a device in which chemical reactions take place in a confinement with typical lateral dimensions below 1 mm; the most typical form of such confinement are microchannels. Microreactors are studied in the field of micro process engineering, together with other devices (such as micro heat exchangers) in which physical processes occur. The microreactor is usually a continuous flow reactor (contrast with/to a batch reactor). Microreactors can offer many advantages over conventional scale reactors, including improvements in energy efficiency, reaction speed and yield, safety, reliability, scalability, on-site/on-demand production, and a much finer degree of process control.
Gas-phase microreactors have a long history but those involving liquids started to appear in the late 1990s. Static micro mixers as split-and-recombine structures became particular important for micro reaction technology. Chip-based flow thermocylers for PCR were early examples of thermal microreactors for liquid processes. Other examples are micro flow-through chip calorimeters. One of the first microreactors with embedded high performance heat exchangers were made in the early 1990s by the Central Experimentation Department (Hauptabteilung Versuchstechnik, HVT) of Forschungszentrum Karlsruhe in Germany, using mechanical micromachining techniques that were a spinoff from the manufacture of separation nozzles for uranium enrichment. As research on nuclear technology was drastically reduced in Germany, microstructured heat exchangers were investigated for their application in handling highly exothermic and dangerous chemical reactions. This new concept, known by names as microreaction technology or micro process engineering, was further developed by various research institutions. An early example from 1997 involved that of azo couplings in a pyrex reactor with channel dimensions 90 micrometres deep and 190 micrometres wide.
Using microreactors is somewhat different from using a glass vessel. These reactors may be a valuable tool in the hands of an experienced chemist or reaction engineer:
One of the simplest forms of a microreactor is a 'T' reactor. A 'T' shape is etched into a plate with a depth that may be 40 micrometres and a width of 100 micrometres: the etched path is turned into a tube by sealing a flat plate over the top of the etched groove. The cover plate has three holes that align to the top-left, top-right, and bottom of the 'T' so that fluids can be added and removed. A solution of reagent 'A' is pumped into the top left of the 'T' and solution 'B' is pumped into the top right of the 'T'. If the pumping rate is the same, the components meet at the top of the vertical part of the 'T' and begin to mix and react as they go down the trunk of the 'T'. A solution of product is removed at the base of the 'T'.
Microreactors can be used to synthesise material more effectively than current batch techniques allow. The benefits here are primarily enabled by the mass transfer, thermodynamics, and high surface area to volume ratio environment as well as engineering advantages in handling unstable intermediates. Microreactors are applied in combination with photochemistry, electrosynthesis, multicomponent reactions and polymerization (for example that of butyl acrylate). It can involve liquid-liquid systems but also solid-liquid systems with for example the channel walls coated with a heterogeneous catalyst. Synthesis is also combined with online purification of the product. Following green chemistry principles, microreactors can be used to synthesize and purify extremely reactive Organometallic Compounds for ALD and CVD applications, with improved safety in operations and higher purity products.
In microreactor studies a Knoevenagel condensation was performed with the channel coated with a zeolite catalyst layer which also serves to remove water generated in the reaction. The same reaction was performed in a microreactor covered by polymer brushes.
A Suzuki reaction was examined in another study with a palladium catalyst confined in a polymer network of polyacrylamide and a triarylphosphine formed by interfacial polymerization:
The combustion of propane was demonstrated to occur at temperatures as low as 300 °C in a microchannel setup filled up with an aluminum oxide lattice coated with a platinum / molybdenum catalyst:
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Microreactor AI simulator
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Microreactor
A microreactor or microstructured reactor or microchannel reactor is a device in which chemical reactions take place in a confinement with typical lateral dimensions below 1 mm; the most typical form of such confinement are microchannels. Microreactors are studied in the field of micro process engineering, together with other devices (such as micro heat exchangers) in which physical processes occur. The microreactor is usually a continuous flow reactor (contrast with/to a batch reactor). Microreactors can offer many advantages over conventional scale reactors, including improvements in energy efficiency, reaction speed and yield, safety, reliability, scalability, on-site/on-demand production, and a much finer degree of process control.
Gas-phase microreactors have a long history but those involving liquids started to appear in the late 1990s. Static micro mixers as split-and-recombine structures became particular important for micro reaction technology. Chip-based flow thermocylers for PCR were early examples of thermal microreactors for liquid processes. Other examples are micro flow-through chip calorimeters. One of the first microreactors with embedded high performance heat exchangers were made in the early 1990s by the Central Experimentation Department (Hauptabteilung Versuchstechnik, HVT) of Forschungszentrum Karlsruhe in Germany, using mechanical micromachining techniques that were a spinoff from the manufacture of separation nozzles for uranium enrichment. As research on nuclear technology was drastically reduced in Germany, microstructured heat exchangers were investigated for their application in handling highly exothermic and dangerous chemical reactions. This new concept, known by names as microreaction technology or micro process engineering, was further developed by various research institutions. An early example from 1997 involved that of azo couplings in a pyrex reactor with channel dimensions 90 micrometres deep and 190 micrometres wide.
Using microreactors is somewhat different from using a glass vessel. These reactors may be a valuable tool in the hands of an experienced chemist or reaction engineer:
One of the simplest forms of a microreactor is a 'T' reactor. A 'T' shape is etched into a plate with a depth that may be 40 micrometres and a width of 100 micrometres: the etched path is turned into a tube by sealing a flat plate over the top of the etched groove. The cover plate has three holes that align to the top-left, top-right, and bottom of the 'T' so that fluids can be added and removed. A solution of reagent 'A' is pumped into the top left of the 'T' and solution 'B' is pumped into the top right of the 'T'. If the pumping rate is the same, the components meet at the top of the vertical part of the 'T' and begin to mix and react as they go down the trunk of the 'T'. A solution of product is removed at the base of the 'T'.
Microreactors can be used to synthesise material more effectively than current batch techniques allow. The benefits here are primarily enabled by the mass transfer, thermodynamics, and high surface area to volume ratio environment as well as engineering advantages in handling unstable intermediates. Microreactors are applied in combination with photochemistry, electrosynthesis, multicomponent reactions and polymerization (for example that of butyl acrylate). It can involve liquid-liquid systems but also solid-liquid systems with for example the channel walls coated with a heterogeneous catalyst. Synthesis is also combined with online purification of the product. Following green chemistry principles, microreactors can be used to synthesize and purify extremely reactive Organometallic Compounds for ALD and CVD applications, with improved safety in operations and higher purity products.
In microreactor studies a Knoevenagel condensation was performed with the channel coated with a zeolite catalyst layer which also serves to remove water generated in the reaction. The same reaction was performed in a microreactor covered by polymer brushes.
A Suzuki reaction was examined in another study with a palladium catalyst confined in a polymer network of polyacrylamide and a triarylphosphine formed by interfacial polymerization:
The combustion of propane was demonstrated to occur at temperatures as low as 300 °C in a microchannel setup filled up with an aluminum oxide lattice coated with a platinum / molybdenum catalyst:
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