Hydrogen bubble characterization in alkaline water electrolysis

This thesis investigates the process of bubble evolution in water electrolysis. Little experimental data exists for conditions found in commercial electrolyzers so that the primary focus was to develop experimental technologies, which would allow measurements under these conditions.; The project was successful in demonstrating that Image Analysis and Laser Scattering Particle Size Analysis were useful in analyzing the bubble evolution phenomena. Hydrogen bubbles were produced from water electrolysis in 1 M K ₂CO₃ at room temperature and pressure using smooth screen, rough screen, crystalline plate, and amorphous-alloy plate electrodes.; Plate electrodes produced more uniform bubble size distribution than screen type cathodes. The mean bubble size, for applied current density of 100 to 250 mA/cm2, decreased in the order of plate electrodes > rough screen > smooth screen electrodes. Bubble size increases with decrease in electrolyte flowrate and increase in current density (except for the rough screen electrode).