“…Then, an extensive range of electrolytes have been employed such as H 2 SO 4 [32,33], KNO 3 [34], HClO 4 [27], NaF [32], Na 2 SO 4 [17,[35][36][37][38][39][40][41] and NaCl (or KCl) [35][36][37][41][42][43][44][45][46][47][48][49]. From all these supporting electrolytes, the role of chloride is important since the colour removal and degradation degree of azo dyes obtained may be enhanced.…”