Vat-Printed Microreactors for Chemical Processing: Residence-Time Distribution, Mixing, Compatibility and Scale-Out

Vat photopolymerisation can fabricate compact microreactors with complex internal mixing structures, but chemical-process performance depends on the realised flow field and material state rather than on channel geometry alone. Channel overcure, roughness, swelling, adsorption, extractables, connector dead volume and pressure deformation can change residence-time distribution (RTD), mixing and reaction selectivity. This review develops a qualification architecture that starts with dimensional and leak verification, then measures RTD and mixing using nonreactive tracers before introducing hazardous or kinetically sensitive chemistry. Material compatibility is treated as time-, temperature- and solvent-specific and must be assessed after post-cure and repeated exposure. Scale-out is separated from geometric scaling: numbering-up requires flow distribution among parallel reactors, while increasing channel size changes transport regimes and cannot be inferred from one microreactor. Reviews of 3D-printed flow chemistry and DLP microfluidics demonstrate the design freedom of the approach but also its material and chemical-resistance limits. The central conclusion is that a printed microreactor is a coupled reactor-material-fluidic system whose qualification must link CAD, realised channel, RTD, chemistry and exposure history.

ER-281 · Version 0.3.