Editing Microreactor (section)

==Challenges==
* Although there have been reactors made for handling particles, microreactors generally do not tolerate particulates well, often clogging.  Clogging has been identified by a number of researchers as the biggest hurdle for microreactors being widely accepted as a beneficial alternative to batch reactors.<ref>{{cite journal |last1=Kumar |first1=Y. |last2=Jaiswal |first2=P. |last3=Panda |first3=D. |last4=Nigam |first4=K.D.P. |last5=Biswas |first5=K.G. |title=A critical review on nanoparticle-assisted mass transfer and kinetic study of biphasic systems in millimeter-sized conduits |journal=Chemical Engineering and Processing - Process Intensification |date=January 2022 |volume=170 |pages=108675 |doi=10.1016/j.cep.2021.108675 |bibcode=2022CEPPI.17008675K }}</ref>  So far, the so-called microjetreactor<ref>{{cite journal |last1=Wille |first1=Ch |last2=Gabski |first2=H.-P |last3=Haller |first3=Th |last4=Kim |first4=H |last5=Unverdorben |first5=L |last6=Winter |first6=R |title=Synthesis of pigments in a three-stage microreactor pilot plant—an experimental technical report |journal=Chemical Engineering Journal |date=August 2004 |volume=101 |issue=1–3 |pages=179–185 |doi=10.1016/j.cej.2003.11.007 |bibcode=2004ChEnJ.101..179W }} and literature cited therein</ref>  is free of clogging by precipitating products. Gas evolved may also shorten the residence time of reagents as volume is not constant during the reaction. This may be prevented by application of pressure.
* Mechanical pumping may generate a pulsating flow which can be disadvantageous. Much work has been devoted to development of pumps with low pulsation.  A continuous flow solution is [[electroosmotic flow]] (EOF).
* The logistics issue and enhanced pressure drop across microreactor limits its applicability in large-scale production units. However, clean solutions are handled well in microreactors.<ref>{{cite journal |last1=Kumar |first1=Y. |last2=Jaiswal |first2=P. |last3=Panda |first3=D. |last4=Nigam |first4=K.D.P. |last5=Biswas |first5=K.G. |title=A critical review on nanoparticle-assisted mass transfer and kinetic study of biphasic systems in millimeter-sized conduits |journal=Chemical Engineering and Processing - Process Intensification |date=January 2022 |volume=170 |pages=108675 |doi=10.1016/j.cep.2021.108675 |bibcode=2022CEPPI.17008675K }}</ref>
* The scale-up of production rates and leakage are quite challenging in case of microreactor. Recently, so called [[nanoparticle]] immobilized reactors are developed to solve logistics and scale-up issues, associated with the microreactors.<ref>{{cite journal |last1=Jaiswal |first1=Pooja |last2=Kumar |first2=Yogendra |last3=Shukla |first3=Raman |last4=Nigam |first4=K. D. P. |last5=Panda |first5=Debashis |last6=Guha Biswas |first6=Koushik |title=Covalently Immobilized Nickel Nanoparticles Reinforce Augmentation of Mass Transfer in Millichannels for Two-Phase Flow Systems |journal=Industrial & Engineering Chemistry Research |date=16 March 2022 |volume=61 |issue=10 |pages=3672–3684 |doi=10.1021/acs.iecr.1c04419 }}</ref> 
*Typically, reactions performing very well in a microreactor encounter many problems in vessels, especially when scaling up. Often, the high area to volume ratio and the uniform residence time cannot easily be scaled.
* [[Corrosion]] imposes a bigger issue in microreactors because area to volume ratio is high. Degradation of few μm may go unnoticed in conventional vessels. As typical inner dimensions of channels are in  the same order of magnitude, characteristics may be altered significantly.