The most important factors influencing the efficiency of the EC process are: electrode materials (see Section 3.1.1), composition of the wastewater including initial pH (see Section 3.1.2) as well as the type and concentrations of the pollutants to be removed, current density, and treatment time (see Section 3.1.3), and to a lesser extent: electrode gap (see Section 3.1.4), supporting electrolyte (see Section 3.1.5), solution temperature, etc. The removal efficiencies (R%) presented in this study have been calculated with Eq. (8):