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==Benefícios==
Utilizar microrreatores é, de certa forma, diferente de utilizar um recipiente de vidro. Estes reatores podem ser uma ferramenta valiosa nas mãos de um químico experiente ou um engenheiro de reação.
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:
*<big><math>\circ</math>Microrreatores Microreactorspossuem typicallycoeficientes havede [[Heattransporte transferde coefficient|heatcalor exchangede, coefficients]]no of at leastmínimo, <math>\mathrm{1\ megawatt per cubic meter per [[kelvin]], up to 500 \frac{MW }{m<sup>−3</sup> ^3\ K<sup>−1}}</supmath>a <!--math>\mathrm{500\ see\frac{MW}{m^3\ talkK}\ page;}</math>enquanto reque exponentsum inrecipiente ChemEngconvencional -->vs.de avidro fewde kilowatts1 inL conventionalpossui glassware<math>\mathrm{\thicksim10\ (1 l flask ~10 \frac{kW }{m<sup>−3</sup> ^3\ K<sup>−1}.}</supmath>). ThusAlém disso, microreactorsmicrorreatores canpodem removeremover heatcalor muchde moremaneira efficientlymais thaneficiente vesselsque andoutros evenrecipientes criticale reactionsaté suchmesmo asreações críticas como [[nitrationNitração|nitrações]]s canpodem beser performedefetuadas safelycom atsegurança a highaltas temperaturestemperaturas.<ref>D.Roberge, L.Ducry, N.Bieler, P.Cretton, B.Zimmermann, Chem. Eng. Tech. 28 (2005) No. 3, [http://www.lonza.com/group/en/company/news/publications_of_lonza.-ParSys-0002-ParSysdownloadlist-0001-DownloadFile.pdf/1_050510_Microreactor%20Technology%20A%20Revolution%20for%20the%20Fine%20Chemical%20and%20Pharmaceutical%20Industries.pdf online available]</ref> ''Hot spotspots'' temperaturesde astemperatura wellassim ascomo thea durationduração ofde highexposição temperaturea expositionalta duetempratura todevido [[exothermic]]itya exotermicidade decreasesdecaem remarkablynotavelmente. ThusAdemais, microreactorsmicrorreatores maypodem allowpossibilitar bettermelhores estudos de [[ChemicalCinética kineticsquímica|kineticcinética]] investigations, becausedevido ao gradiente de temperatura local temperature— gradientsque affectingafeta reactionas ratestaxas arede muchreação smaller— thanser inmuito anyinferior batchque vesselem qualquer recipiente de batelada. HeatingAquecer andou coolingresfriar aum microreactormicrorreator istambém alsoé muchdeverasmente quickermais andrápido [[operatinge temperature]]sa cantemperatura bemínima asde lowoperação aspode chegar a <math>\mathrm{-100^oC\ −100 °C.}</math> AsComo aresultado resultde ofuma thetransferência superiorde heatcalor transfersuperior, reactiona temperaturestemperatura mayreacional bepode muchser highermuito thanmaior inque conventionalem batch-reactorsreatores convencionais. ManyMuitas lowreações temperaturea reactionsbaixas astemperaturas organo-metal— chemistrycomo canquímica beorganometálica performed— inpodem microreactorsser atrealizadas temperaturesa of<math>\mathrm{-10^oC}</math> −10 °Ccontra rathera thanfaixa −50 °C<math>\mathrm{-50^oC to\leftrightarrow-78^oC}</math>utilizada −78 °C asem inequipamentos laboratorye glasswarevidrarias equipmentlaboratoriais.
* Microreactors are normally operated continuously. This allows the subsequent processing of unstable intermediates and avoids typical batch [[Work-up (chemistry)|workup]] delays. Especially low temperature chemistry with reaction times in the millisecond to second range are no longer stored for hours until dosing of reagents is finished and the next reaction step may be performed. This rapid work up avoids decay of precious intermediates and often allows better selectivities.<ref>T.Schwalbe, V.Autze, G.Wille: Chimica 2002, 56, p.636, see also [http://www.mrsp.net/MRSP_Chimica_Oggi.pdf Microflow Synthesis]</ref>
<big><math>\circ</math>Microrreatores são operados continuamente. Isso permite o processamento subsequente de intermediários instáveis e evita contratempos típicos de reatores convencionais. Especialmente na química de baixa temperatura com tempo de reação da ordem de milissegundos não são mais armazenadas por horas até o dosamento de reagentes é terminado e a próxima reação seja executada. Esse trabalho rápido poupa o decaimento de intermediários desejados e frequentemente propicia melhor seletividade.<ref>T.Schwalbe, V.Autze, G.Wille: Chimica 2002, 56, p.636, see also [http://www.mrsp.net/MRSP_Chimica_Oggi.pdf Microflow Synthesis]</ref>
* Continuous operation and mixing causes a very different concentration profile when compared with a batch process. In a batch, [[reagent]] A is filled in and reagent B is slowly added. Thus, B encounters initially a high excess of A. In a microreactor, A and B are mixed nearly instantly and B won't be exposed to a large excess of A. This may be an advantage or disadvantage depending on the [[reaction mechanism]] - it is important to be aware of such different concentration profiles.
* Although a bench-top microreactor can synthesize chemicals only in small quantities, scale-up to industrial volumes is simply a process of multiplying the number of microchannels. In contrast, batch processes too often perform well on R&D bench-top level but fail at batch pilot plant level.<ref>T.Schwalbe, V.Autze, M. Hohmann, W. Stirner: Org.Proc.Res.Dev 8 (2004) p. 440ff, see also [http://www.mrsp.net/MRSP_lo-res.pdf Continuous process research and implementation from laboratory to manufacture]</ref> ▼<big><math>\circ</math>Operação contínua e misturas causam um perfil diferente de concentração quando comparado com um processo em batelada. Na batelada, um reagente A é adicionado e um reagente B é adicionado lentamente. Outrossim B encontra inicialmente um alto excesso de A. Em um microrreator, A e B são misturados quase instantaneamente e B não será exposto a um excesso de A. Essa característica pode tanto ser uma vantagem como uma desvantagem dependendo do mecanismo reacional — é importante levar em conta os diferentes perfis de concentração.
* Pressurisation of materials within microreactors (and associated components) is generally easier than with traditional batch reactors. This allows reactions to be increased in rate by raising the temperature beyond the boiling point of the solvent. This, although typical Arrhenius behaviour, is more easily facilitated in microreactors and should be considered a key advantage. Pressurisation may also allow dissolution of reactant gasses within the flow stream. ▼
▲* <big><math>\circ</math>Although a bench-top microreactor can synthesize chemicals only in small quantities, scale-up to industrial volumes is simply a process of multiplying the number of microchannels. In contrast, batch processes too often perform well on R&D bench-top level but fail at batch pilot plant level.<ref>T.Schwalbe, V.Autze, M. Hohmann, W. Stirner: Org.Proc.Res.Dev 8 (2004) p. 440ff, see also [http://www.mrsp.net/MRSP_lo-res.pdf Continuous process research and implementation from laboratory to manufacture]</ref>
▲* <big><math>\circ</math>Pressurisation of materials within microreactors (and associated components) is generally easier than with traditional batch reactors. This allows reactions to be increased in rate by raising the temperature beyond the boiling point of the solvent. This, although typical Arrhenius behaviour, is more easily facilitated in microreactors and should be considered a key advantage. Pressurisation may also allow dissolution of reactant gasses within the flow stream.
==Problemas==
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