Simulation of cobalt dissolution from cemented carbide with different cobalt content in molten salt electrolysis

Cemented carbide is a composite material consisting of a hard phase, which is tungsten carbide, and a binder phase of Co, whose content influences the dissolution process of cemented carbide. Finite element simulations of Co dissolution during the electrolysis of the molten salt of cemented carbide were conducted for different Co contents using the numerical simulation software COMSOL Multiphysics. According to the changes in the mass of dissolved anode material and in the Co2+ concentration in the molten salt at various times, the time of complete Co dissolution increases in cemented carbide with low Co content because the discontinuity of the Co phase leads to secondary dissolution of Co in the dissolution process; with the increase in Co content, the Co phases in cemented carbide are gradually connected, Co can always be dissolved, and the time of complete dissolution is shortened. In cemented carbide with high Co content, the time of complete Co dissolution increases with increasing Co content. The dissolution law of cemented carbide with different Co content, combined with the effect of applied potential on the dissolution of cemented carbide derived from the simulation, provides a feasible approach to improve the current efficiency and shorten the actual time of complete dissolution of Co in cemented carbide.