Key to the success of Flow Chemistry is the scale that reactions are performed at! Process advantages are gained from rapid mixing & efficient heat transfer! Flow Chemistry is a technique that can be used in the lab to develop synthetic routes & in manufacturing to produce materials that would be inaccessible using conventional batch vessels.
Our Flow Chemistry journey started in 2000 at The University of Hull (UK), with postgraduate research sponsored by Novartis (Basel, CH). Those early years highlighted to us the key drivers for Industry & the role that Academia can play in new technology development & proof of concept demonstration! Starting Chemtrix in 2008, we continued to work closely with Academia & Industry to develop the tools needed to advance the use of Flow Chemistry in teaching, research & manufacturing environments - resulting in our Scalable Flow Chemistry portfolio.
WHAT IS FLOW CHEMISTRY?
In Flow Chemistry, two or more reagents are continuously pumped into a Flow Reactor where they are mixed & reacted under thermal control. The products are continuously collected for the time needed to prepare the material target. It is this feature that allows Flow Chemistry to be used for research at the mg-scale & production at the multi-metric tonne scale.
ADVANTAGES OF FLOW CHEMISTRY
Flow Chemistry has some important advantages that arise from the small reactor size! Mixing can be achieved in the ms to sec range & the high surface to volume ratio (typically x1000's larger than batch) enables rapid heating or cooling of the reaction mass, resulting in safer operation of exothermic processes & cleaner products. Reaction temperatures above a solvents atmospheric boiling point are routinely used to intensify processes, leading to shorter reaction times, increased product selectivity & a high unit productivity.
The small hold-up volume is advantageous for process optimisation, enabling rapid parameter screening (time, temperature, concentration, stoichiometry, pressure), using small quantities of material. For production, a small hold-up volume enhances process safety, as only a small quantity of reactive or unstable intermediate is present at any one time.
Operationally, process intensification gives significant improvements in energy efficiency, safety & reliability. An ease of unit replication (scale-out) allows multiple identical set-ups to be deployed, providing on-site / on-demand production in different locations, securing supply chains.
A Flow Reactor (or Micro Reactor) needs to perform several functions in order to realise the advantages of Flow Chemistry. It must thermally control reagent feeds, mix the reagents in the specified order, control any heat of reaction, provide enough residence volume to complete the reaction & quench the process (thermally or chemically) to deliver a stable, high quality product stream. To achieve this, the reactor must be capable of being heated or cooled, have sufficient heat transfer area for the targeted process flows & be fabricated from a long-lasting material of construction for extended periods of operation.
At the lab-scale it is possible to have all of these features in a single module (Labtrix & GramFlow), with various standard designs & volumes available with SOR-mixers. When increases in throughput are needed, an increase in the surface area for heat exchange is needed & we produce separate modules with pre-heating, mixing & residence time functionality (KiloFlow, Protrix & Plantrix), these are flexibly combined in a holder by the User to access the required reactor configuration (A+B to A+B+C+D for example).
Chemtrix Flow Reactors are fabricated from glass at the lab-scale & 3MTM silicon carbide for pilot & full-scale production, giving unrivalled chemical compatibility & thermal control.
DRIVERS OF FLOW CHEMISTRY
Whilst the implementation drivers for Flow Chemistry & Process Intensification vary across the Chemical Industry, the technical & operational benefits largely stem from increased process control!
1. SAFE USE OF EXTREME CONDITIONS
- Efficient mixing
- Excellent thermal control
- Process intensification of hazardous reactions
2. REDUCED DEVELOPMENT TIME
- Small hold-up volume
- Rapid reaction optimisation
- Minimal scale-up steps
3. IMPROVED PROCESS CONTROL
- High level of reaction control
- Process reproducibility
- Quality by design (QbD)
4. REDUCED REACTION COSTS
- Increased product quality
- Reduced safety investment
- Higher unit productivity