Micro Reactors

Microreactors are miniaturised continuous flow devices with reaction channel dimensions typically in the range of 100 µm to 1000 µm (0.1–1.0 mm), fabricated in chemically inert materials including borosilicate glass, silicon, stainless steel (SS 316L), Hastelloy C-276, and polymer substrates such as PTFE and PFA. The defining characteristic of microreactors is their exceptionally high surface-area-to-volume ratio — orders of magnitude greater than batch vessels — which enables near-instantaneous heat transfer and mass transfer rates that are physically unachievable in conventional stirred-tank reactors. In a microreactor, reagent streams are introduced through precision-metered inlet ports and merged at a mixing junction — typically a T-mixer, Y-mixer, or interdigital multi-lamination mixer — before entering the structured reaction channel. Mixing occurs through diffusion, engineered flow patterns (split-and-recombine, chaotic advection), or ultrasonic enhancement, with mixing times as low as 1–10 milliseconds achievable. The reaction channel — which may be serpentine, spiral, or straight depending on residence time requirements — is embedded within a thermally controlled block, maintaining isothermal conditions across the reaction zone with temperature control precision of ±0.5°C or better.

The combination of fast mixing and excellent heat transfer enables access to reaction conditions that are either impractical or hazardous in batch: flash chemistry at −78°C and below, high-temperature superheating above the atmospheric boiling point under pressure, and handling of thermally unstable or highly exothermic reaction intermediates with full safety margin. Residence time control is achieved through channel volume and flow rate, with typical residence windows from 100 milliseconds to 30 minutes. Multi-step synthesis is achievable by connecting microreactor modules in series, with inline reagent addition and quenching at each stage.