Microreactors are increasingly used for green and safe chemical processes owing to their benefits of superior mass and heat transfer

increased yield

safety

and simplicity of control. However

immobilizing catalysts in microreactors remains challenging. In this investigation

a technique for creating Cu

2

O/montmorillonite catalyst coating

using electrostatic attraction for layer-by-layer self-assembly

was proposed. The montmorillonite film's morphology and thickness could be efficiently regulated by adjusting the degree of exfoliation and surface charge of montmorillonite

alongside layer-by-layer coating times. The Cu

2

O nanoparticles were immobilized using the flow deposition approach. The resulting Cu

2

O@montmorillonite-film-coated capillary microreactor successfully transformed glycerol into dihydroxyacetone. The conversion of glycerol and product selectivity could be controlled by adjusting the molar ratio of reactants

temperature

residence time

and Cu

2

O loading. The maximum glycerol conversion observed was 47.6%

with a 27% selectivity toward dihydroxyacetone. The study presents a technique for immobilizing montmorillonite-based catalyst coatings in capillary tubing

which can serve as a foundation for the future application of microreactors in glycerol conversion.