In the spectrum of MB+ (Fig. 6), several peaks are observed in the fingerprint region (from about 1500 to 500 cm−1) with a sharp peak at the region 1600 cm−1 due to C N and C C double bond. The broad peaks, for example, at 2250 cm−1 are due to S C N bond. However, all of these features were removed when the electrolysis was performed at +0.7 V. This FTIR disappearance, consistent with UV–visible spectral analysis, indicates that MB molecules were disintegrated in the presence of KCl. In the other words, followed by hypochlorite action, MB molecules were oxidized into numerous inorganic compounds, which might be CO2, H2O, NO3−, SO42−