Flow Chemistry: Process Intensification through Microreactor Technology
Igor Plazl,
Professor,
University of Ljubljana
A substantial amount
of publications each year demonstrate how through the application of
microprocess engineering significant benefits can be obtained concerning
product yield, purity and time needed for chemical and biochemical transformations,
compared to the equivalent bulk reactions [1]. The microreactor technology demonstrated the advantages of
microfluidic devices for very efficient performing of chemical and biochemical
processes at controlled and repeatable conditions. Recently, the new concepts
such as continuous processing, flow chemistry, high-throughput screening, and
process intensification, have been established in order to open novel pathways
in process design and engineering. The process intensification provides insights into
the different scales at which process intensification can be employed.
Stankiewicz and Moulijn [2] defined process intensification as the development
of novel and sustainable equipment that compared to the existing
state-of-the-art, produces dramatic process improvements related to equipment
sizes, waste production, and other factors. No doubt, process intensification
through microreactor applications clearly hold the potential to revolutionize (bio)chemical
synthesis, but scarce articles demonstrate specific suggestions for possible
replacement of existent industrial processes. On the other hand, a number of highly
innovative and systematic approaches, protocols, tools, and strategies has
currently been developed in both industry and academia, all to minimize the gap
between research and industry, and to define a smooth transfer of lab-on-a-chip
to the industrial environment. To meet these challenges, we must advance the
field from (bio)catalyst discovery to (bio)catalytic microprocess design. This
will require not only a new level of understanding of reaction mechanisms and
transport phenomena at the micro scale, but also the development of relevant
computational tools [3].In
this work, the microscale (bio)process development based on
scale-up/numbering-up concept in combination with modeling-based optimization
is presented. The main features of microscale systems are reflected in fluid
dynamics, therefore the understanding of fundamental mechanisms involved in
fluid flow characteristics at the micro scale is essential since their
behaviour affects the transport phenomena and microfluidic applications.
Theoretical description of transport phenomena and the kinetics at the micro
scale is discussed and illustrated on the cases of a lattice Boltzmann
simulations for flow distribution in the packed bed microreactor “between
two-plates” and the biocatalytic enzyme surface reaction.
|