Multi-component flow and reaction kinetics in photocatalytic microreactors

Microreactors demonstrate exceptional potential for improving the reaction efficiency in photocatalytic water splitting. However, a critical knowledge gap persists in the comprehensive modeling of complex interactions within these systems, including the coupling of catalytic surface reactions, fluid dynamics, heat transfer, and mass transport at the mesoscopic scale. To address this challenge, we develop a mesoscale-coupled lattice Boltzmann framework that synergistically integrates establishing a multi-component fluid model that integrates the lattice Boltzmann method with the Shan-Chen pseudopotential. This model effectively captures bubble dynamics involving diffusion, aggregation, and expulsion, revealing their critical role on catalytic efficiency. Increasing inlet velocities enhances flow complexity, fostering bubble formation and expulsion, which promotes reactor performance. Smaller catalyst units, while lowering the average reaction rate, increase reaction sites, reduce bubble size, and enhance bubble dispersion. This work provides a robust modeling framework for studying the multiphysics coupling in photocatalytic microreactors, offering valuable insights for their design and optimization in a variety of applications.