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Microreaction technology is an interdisciplinary field that has gained significant momentum in recent years due to the numerous advantages it offers compared to conventional systems in terms of enhanced heat and mass transfer and safer operation. The experimental efficiency achieved through the well-defined conditions offered by microchannel reactors has been utilised to elucidate intrinsic reaction kinetics, often in reaction spaces that were previously unexplored. In this review, we discuss prospects for advancing catalytic process development by combined application of microstructured flow reactors with techniques for in situ catalyst characterisation and mathematical optimisation.

Microreactor platforms represent advanced tools in reaction engineering for the quick development of reliable kinetic models. Experiments can be performed with a better reaction temperature control, enhanced heat and mass transfer and mixing of reactants. However, the effectiveness of the model identification procedure is strictly related to the execution of properly designed experiments, allowing elucidation of the reaction mechanisms and providing a precise estimation of the kinetic parameters. In this paper a model-based design of experiments (MBDoE) approach is proposed where experiments are designed for both discriminating among competing models and for improving the estimation of kinetic parameters. The procedure is tested on a real case study related to the identification of kinetic models of methanol oxidation on silver catalyst.

Anodically bonded etched silicon microfluidic devices that allow infrared spectroscopic measurement of solutions are reported. These extend spatially well-resolved in situ infrared measurement to higher temperatures and pressures than previously reported, making them useful for effectively time-resolved measurement of realistic catalytic processes. A data processing technique necessary for the mitigation of interference fringes caused by multiple reflections of the probe beam is also described.

An experimental and theoretical study of capillary gas/liquid phase microseparators is presented. The device studied comprises a main microchannel with a set of capillaries fabricated to each side so that the liquid (wetting) phase can be separated from the gas (non-wetting) phase due to capillary effects. Different units are employed with different characteristics of capillaries (constant or tapered cross-sectional area and capillary size). We study how complete separation depends on the externally controlled pressure difference at the liquid and the gas outlet and how separation is affected by the imposed inlet flow rate. The results demonstrate that the operability pressure window becomes narrower as the fluid flow rates increase, and reveal discrepancies with theoretical predictions based on a simple Hagen–Poiseuille formulation. This is addressed by a new equation that takes into account interface curvature effects, and is found to be in qualitative agreement with the experimental results. In addition, we perform CFD simulations observing the emergence of interface breaking at high flow rates.