Editing Microreactor (section)

==Applications==
[[Image:Syrris Chip.jpg|right|frame|Glass microreactors involve microfabricated structures to allow [[flow chemistry]] to be performed at a microscale. Applications include compound library generation, process development, and compound synthesis]]

===Synthesis===
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 reaction]]s 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.<ref name=Watts/> Following [[green chemistry]] principles, microreactors can be used to synthesize and purify extremely reactive [[Organometallic]] Compounds for [[Atomic Layer Deposition|ALD]] and [[Chemical vapor deposition|CVD]] applications, with improved safety in operations and higher purity products.<ref>''Method of Preparing Organometallic Compounds Using Microchannel Devices'', '''2009''', Francis Joseph Lipiecki, Stephen G. Maroldo, Deodatta Vinayak Shenai-Khatkhate, and Robert A. Ware, [http://www.freepatentsonline.com/y2009/0023940.html US 20090023940]</ref><ref>''Purification Process Using Microchannel Devices'', '''2009''', Francis Joseph Lipiecki, Stephen G. Maroldo, Deodatta Vinayak Shenai-Khatkhate, and Robert A. Ware, [http://www.freepatentsonline.com/y2009/0020010.html US 20090020010]</ref>

In microreactor studies a [[Knoevenagel condensation]]<ref>{{cite journal |last1=Lai |first1=Sau Man |last2=Martin-Aranda |first2=Rosa |last3=Yeung |first3=King Lun |title=Knoevenagel condensation reaction in a membrane microreactor |journal=Chemical Communications |date=7 January 2003 |issue=2 |pages=218–219 |doi=10.1039/b209297b |pmid=12585399 }}</ref> 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.<ref>{{cite journal |last1=Costantini |first1=Francesca |last2=Bula |first2=Wojciech P. |last3=Salvio |first3=Riccardo |last4=Huskens |first4=Jurriaan |last5=Gardeniers |first5=Han J. G. E. |last6=Reinhoudt |first6=David N. |last7=Verboom |first7=Willem |title=Nanostructure Based on Polymer Brushes for Efficient Heterogeneous Catalysis in Microreactors |journal=Journal of the American Chemical Society |date=11 February 2009 |volume=131 |issue=5 |pages=1650–1651 |doi=10.1021/Ja807616z |pmid=19143524 |bibcode=2009JAChS.131.1650C }}</ref>

:[[Image:Knoevenagelmicroreactor.png|400px|Knoevenagel condensation application]]
A [[Suzuki reaction]] was examined in another study<ref>{{cite journal |last1=Uozumi |first1=Yasuhiro |last2=Yamada |first2=Yoichi M. A. |last3=Beppu |first3=Tomohiko |last4=Fukuyama |first4=Naoshi |last5=Ueno |first5=Masaharu |last6=Kitamori |first6=Takehiko |title=Instantaneous Carbon−Carbon Bond Formation Using a Microchannel Reactor with a Catalytic Membrane |journal=Journal of the American Chemical Society |date=December 2006 |volume=128 |issue=50 |pages=15994–15995 |doi=10.1021/ja066697r |pmid=17165726 |bibcode=2006JAChS.12815994U }}</ref> with a palladium catalyst confined in a [[polymer network]] of [[polyacrylamide]] and a [[triphenylphosphine|triarylphosphine]] formed by [[interfacial polymerization]]:
 
:[[Image:Suzukimicroreactorreaction.png|400px|Suzuki reaction application]]

The [[combustion]] of [[propane]] was demonstrated to occur at temperatures as low as 300&nbsp;°C in a microchannel setup filled up with an [[aluminum oxide]] lattice coated with a [[platinum]] / [[molybdenum]] catalyst:<ref>{{cite journal |last1=Guan |first1=Guoqing |last2=Zapf |first2=Ralf |last3=Kolb |first3=Gunther |last4=Men |first4=Yong |last5=Hessel |first5=Volker |last6=Loewe |first6=Holger |last7=Ye |first7=Jianhui |last8=Zentel |first8=Rudolf |title=Low temperature catalytic combustion of propane over Pt-based catalyst with inverse opal microstructure in a microchannel reactor |journal=Chem. Commun. |date=2007 |issue=3 |pages=260–262 |doi=10.1039/b609599b |pmid=17299632 }}</ref>

:[[Image:PropaneCombustionInmicrochannelreactor.png|400px|Propane combustion application]]

=== Enzyme catalyzed polymer synthesis ===
Enzymes immobilized on solid supports are increasingly used for greener, more sustainable chemical transformation processes. > enabled to perform heterogeneous reactions in continuous mode, in organic media, and at elevated temperatures. Using microreactors, enabled faster polymerization and higher molecular mass compared to using batch reactors. It is evident that similar microreactor based platforms can readily be extended to other enzyme-based systems, for example, high-throughput screening of new enzymes and to precision measurements of new processes where continuous flow mode is preferred. This is the first reported demonstration of a solid supported enzyme-catalyzed polymerization reaction in continuous mode.

===Analysis===
Microreactors can also enable experiments to be performed at a far lower scale and far higher experimental rates than currently possible in batch production, while not collecting the physical experimental output. The benefits here are primarily derived from the low operating scale, and the integration of the required sensor technologies to allow high quality understanding of an experiment. The integration of the required [[Chemical synthesis|synthesis]], purification and [[Analytical chemistry|analytical]] capabilities is impractical when operating outside of a microfluidic context.

====NMR====

Researchers at the Radboud University Nijmegen and Twente University, the Netherlands, have developed a microfluidic high-resolution NMR flow probe. They have shown a model reaction being followed in real-time. The combination of the uncompromised (sub-Hz) resolution and a low sample volume can prove to be a valuable tool for flow chemistry.<ref>{{cite journal |last1=Bart |first1=Jacob |last2=Kolkman |first2=Ard J. |last3=Oosthoek-de Vries |first3=Anna Jo |last4=Koch |first4=Kaspar |last5=Nieuwland |first5=Pieter J. |last6=Janssen |first6=Hans (J. W. G.) |last7=van Bentum |first7=Jan (P. J. M.) |last8=Ampt |first8=Kirsten A. M. |last9=Rutjes |first9=Floris P. J. T. |last10=Wijmenga |first10=Sybren S. |last11=Gardeniers |first11=Han (J. G. E.) |last12=Kentgens |first12=Arno P. M. |title=A Microfluidic High-Resolution NMR Flow Probe |journal=Journal of the American Chemical Society |date=15 April 2009 |volume=131 |issue=14 |pages=5014–5015 |doi=10.1021/ja900389x |pmid=19320484 |bibcode=2009JAChS.131.5014B |url=https://repository.ubn.ru.nl//bitstream/handle/2066/76115/76115.pdf }}</ref>

====Infrared spectroscopy====

Mettler Toledo and [[Bruker Optics]] offer dedicated equipment for monitoring, with [[attenuated total reflectance]] spectrometry (ATR spectrometry) in microreaction setups. The former has been demonstrated for reaction monitoring.<ref>{{cite journal |last1=Carter |first1=Catherine F. |last2=Lange |first2=Heiko |last3=Ley |first3=Steven V. |last4=Baxendale |first4=Ian R. |last5=Wittkamp |first5=Brian |last6=Goode |first6=Jon G. |last7=Gaunt |first7=Nigel L. |title=ReactIR Flow Cell: A New Analytical Tool for Continuous Flow Chemical Processing |journal=Organic Process Research & Development |date=19 March 2010 |volume=14 |issue=2 |pages=393–404 |doi=10.1021/op900305v }}</ref>  The latter has been successfully used for reaction monitoring<ref>{{cite journal |last1=Minnich |first1=Clemens B. |last2=Küpper |first2=Lukas |last3=Liauw |first3=Marcel A. |last4=Greiner |first4=Lasse |title=Combining reaction calorimetry and ATR-IR spectroscopy for the operando monitoring of ionic liquids synthesis |journal=Catalysis Today |date=August 2007 |volume=126 |issue=1–2 |pages=191–195 |doi=10.1016/j.cattod.2006.12.007 }}</ref>  and determining dispersion characteristics<ref>{{cite journal |last1=Minnich |first1=Clemens B. |last2=Sipeer |first2=Frank |last3=Greiner |first3=Lasse |last4=Liauw |first4=Marcel A. |title=Determination of the Dispersion Characteristics of Miniaturized Coiled Reactors with Fiber-Optic Fourier Transform Mid-infrared Spectroscopy |journal=Industrial & Engineering Chemistry Research |date=16 June 2010 |volume=49 |issue=12 |pages=5530–5535 |doi=10.1021/ie901094q }}</ref>  of a microreactor.