Ozonation of methylene blue and its fate study using LC-MS/MS

In this study, ozone was used to degrade an organic compound of methylene blue dye. The methylene blue was treated with ozonation using ozone generator and the degradation was observed as dye decolorization. Various parameters of ozonation such as contact time, pH, and temperature were chosen. The maximum ozonation of methylene blue degradation was at pH and contact time of 11 and 13 min, respectively. The effect of temperature on the destruction of methylene blue with ozone was obtained the highest result at temperature 35 °C. The LC-MS/MS results showed that ozonation caused degradation of methylene blue producing a compound with molecular weight of 208 g/mol as the unstable compound of N-(4-nitrophenyl) butanamide (C10H12N2O3). Finally, it formed stable fraction compound of 1-nitrocyclohexene (C6H9NO2) with molecular weight of 127 g/mol which much safer and reduce the harmness of methylene blue in waste.