Nanoparticle-enhanced hydrogen separation from CO2 in cylindrical and cubic microchannels: A 3D computational fluid dynamics simulation

Abstract

In this study, hydrogen is purified from its mixture with CO2 using Monoethanolamine-based nanofluids in a T-junction microchannels at dynamic conditions with various lengths and diameters simulated with the aid of computational fluid dynamics. Navier-Stokes and continuity equations, reaction rate, and two-phase transport models are utilized in COMSOL Multiphysics software for this investigation. The impacts of different parameters on hydrogen purification such as solvent and nanoparticles (NPs) concentrations, and channel geometry are investigated. By decreasing the channel diameter, hydrogen purification increases. Furthermore, an increase in channel length enhances hydrogen purification exponentially. Results reveals that the cubic channel has higher hydrogen purification compared to the cylindrical channel. Besides, hydrogen is purified to 98.83% in 15 mm length. NPs concentration has an optimum value after which further increase in NPs concentration reduces in hydrogen purification. Among different NPs in this research, TiO2 has maximum hydrogen purification efficiency at 0.06 wt% which hydrogen purity can be increased up to 98.62 wt%.