Electrocatalytic urea removal is a promising technology for artificial kidney dialysis and wastewater treatment. Urea electrooxidation was studied on a variety of nickel electrocatalysts modified with Cr, Mo, Mn, and Fe with varying electrochemically active surface and roughness. Mass transfer limits were observed for urea oxidation at physiological concentrations (10 mM). Urea oxidation kinetics were explored at higher concentrations (200 mM), showing improved performance during polarization, but lower currents per active site. A simplified dialysis model was developed to examine the relationship of mass transfer coefficients and extent of reaction on flowrate, composition, and pH of the reacting stream. For a nickel hydroxide catalyst, the model shows that a minimum electrode area of 1314 cm ² is needed for continuous operation. This research combines experimental data and a computational dialysis model for a simplified continuous dialysis system, highlighting the potential of these catalysts and paving the way for future improvements.