Treatment of diazo dye Reactive Green 19 by anodic oxidation on a boron-doped diamond electrode

•Reactive Green 19 was successfully degraded on a boron-doped diamond electrode.•The effect of the most important factors on color and TOC removal was studied.•Process variables exhibited different effects on color and TOC removal.•Under appropriate conditions complete decolorization and extended mineralization were achieved.

The anodic oxidation of diazo dye Reactive Green 19 on a boron-doped diamond electrode was investigated. A membrane-free reactor was used to evaluate the effect of chloride concentration (0–0.5 M), current density (100–500 A m−2), pH (3–11) and stirring rate (250–750 rpm) on color and TOC removal. Complete decolorization was obtained in less than 30 min, whereas total mineralization was never achieved within 3 h of electrolysis. Color removal was significantly enhanced by increasing chloride concentration and, to a lesser extent, current density and stirring rate. TOC removal was positively affected by current density, pH and chloride concentration.

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