Show menu
Key expertise

Multipurpose Flow Chemistry

In flow chemistry, a chemical reaction is run in a continuously flowing stream rather than in batch production. Flow chemistry isn’t new but was previously restricted to large volume chemicals with on purpose manufacturing plants. New equipment and technologies allow to use modular and flexible equipment for custom synthesis of small volume chemicals.
Flow Chem

Key advantages of Flow Chemistry

Technical features of Flow chemistry compared to batch translate into key advantages: High exchange surface to volume ratio – Conditions precisely controlled – Higher selectivity


In Flow conditions, higher exchange surface to volume ratio and smaller volume allow to perform reactions safely compared to batch:

  • X 200 exchange surface to volume ratio vs batch
  • Conditions precisely controlled
  • Lower risk of adverse events
  • In situ synthesis of hazardous intermediates 


Flow chemistry allows safety and competitive economics for the reshoring of processes previously only performed in Asia:

  • Faster reactions: hours to minutes
  • Less idle time versus batch processes
  • Possibly no intermediate purification step

The initial development time is reduced, and upscaling facilitates compared to batch chemistry.

Flow Chemistry requires lower investment for incremental capacity increase and lower OPEX. Flexible production of required quantities without limitations by batch size 

Possible Intellectual Property generation with new synthesis pathways or conditions distinct from batch

Improved environmental footprint

Significant reduction of environmental footprint compared to batch:

  • ~30% Energy consumption reduction
  • FROM 50% TO 80% reduction of solvent consumption
  • ~50% Reduction of environmental footprint

Lower need of solvent for mixing and calorific transfer as volume is lower with a high surface exchange

Possibly no need of (solvent-consuming) intermediate purification step

Homothetic equipment between laboratory scale and manufacturing scale 

From Lab 

  • Laboratory equipment for fast conditions screening then homothetic implementation for the upscaling to manufacturing scale  
  • Capacity: 60g/h (non GMP)

To Manufacturing 

  • cGMP Manufacturing at ton scale (50Kg/day – 2 temperature zones)
  • Process Analytical Technology (PAT) tools coupled with Chemometrics competencies 
  • Continuous work-up (2 cascaded mixer-settlers)


Nitration is a typical example of a reaction which is no longer performed in Europe due to safety:
  • Corrosive and hazardous reagent: HNO3
  • Risk of overnitration
  • Explosiveness of nitrated byproducts

Nitration can be combined with hydrogenation to obtain amines.


Possibility to safely perform electrophilic or nucleophilic fluorination reactions
  • Hazardous reagents: F2(gaseous), HF
  • Risk of oxidation side reaction

Possibility to redesign synthesis pathways with late-stage fluorination



Safe and selective chlorination using Cl2
  • Explosive nature of Cl2 with organic volatiles
  • Highly exothermic reaction
  • Risk of over chlorination

Flow chemistry allows to mitigate several risks associated with batch reactions

Hazardous reagents

  • Cyanation: possibility to strictly control HCN through neutralization at the end of the reaction
  • Reaction steps using hydrazine

Unstable intermediates

  • Oxidation: in-situ formation of unstable Caro’s acid
  • Diazotization: possibility to produce in situ the unstable diazonium intermediate then perform the next step

Reaction conditions

  • Hydrogenation: H2 pressure management

Ability to perform reactions above solvents boiling point

Case study: safe and selective dinitration

>35% of FDA recently approved drugs need at least a nitration step in their manufacturing process. About 35% need at least a chlorination step and about 30% need at least a fluorination step, to mention only these three reaction families.

Over the last 20 years, the industrialization of such reactions has become rare in Europe. Industrial plants have some difficulties of maintaining their implementation in an acceptable environmental and safety conditions with regards to local regulations. In fact, a large part of the production of APIs has been exported to Asia. A crisis such as the Covid-19 is a clear indication of the fragility of the drug supply chain in western geographical areas.

Seqens is investing in Flow chemistry technology to improve competitiveness and safety for custom synthesis.


Discover other R&D services


Analytical Platform

Analytical Platform

Seqens provides GMP testing on Active Pharmaceutical Ingredients (API) and excipients. We have an extensive team focused on the development and clinical phase appropriate validation of sensitive and specific analytical methods

Know more



Biocatalysis is the usage of enzymes as catalysts of chemical reactions. Learn more about Seqens extensive expertise.

Know more



40% of drugs fail in preclinical trials due to bioavailability issues. Seqens has a strong expertise to support you regarding bioavailability challenges.

Know more


Characterization of APIs

Physical Characterization Testing Capabilities includes a full set of advanced technologies

Know more

Drug Conjugates

Drug Conjugates

The field of drug conjugates is emerging, with the possibility to achieve 2 functions with one (bifunctional) compound, usually allowing targeted therapies or improved bioavailability properties.

Know more



In the pharmaceutical industry, lipids are core excipients in the development of drug delivery systems. Lipids can be used in most dosage forms as support vehicles, solubilizers, permeation enhancers, stabilizers, transfection agents and release rate modifiers.

Know more



Seqens strongly believes in the potential of new cutting-edge technologies to improve the use and efficiency of existing APIs. To support its customers, Seqens offers a range of drug delivery polymers.

Know more

Solid State

Solid State characterization

The need to investigate the solid state properties of APIs has become important in the pharmaceutical development industry. Physical properties can vary widely between batches, leading to batch-to-batch variability.

Know more

Synthetic Biology

Synthetic Biology for bioinspired and sustainable innovations

Part of Seqens group, Alganelle is an innovative biotechnology company at the cutting edge of synthetic biology and metabolic engineering.

Know more