The DIFfusion of Actinides in EleCtrorefiner (DIFAC) computer code has been developed and is used to calculate the variation of the anode potential with time during constant current anodic dissolution of U, Zr, and U-Zr alloy in molten LiCl-KCl eutectic. A few algorithms are proposed within the framework of the DIFAC code for modeling the activation and concentration overpotentials during anodic dissolution. These algorithms are based on an iterative search procedure and would later be applied to modeling the electrorefining of a multicomponent metallic fuel system.