Anodic oxidation of phenolics found in coal conversion effluents

Abstract Solutions of phenol, o‐cresol, p‐cresol, 2,3‐xylcnol, 3,4‐xylenol, resorcinol, and catechol at concentrations below I g/L were oxidized at constant current on a packed bed lead dioxide electrode with electrolyte recirculation. The effects of applied current and initial concentration on the extent of oxidation with time were explored. The observed ranking in ease of oxidation was phenol > 2,3‐xylenol > resorcinol > p‐cresol > 3,4‐xylenol > o‐cresol. Although the phenolics were largely destroyed, organic degradation products of the quinone and hydroquinone type remained in solution. A mixture of five monohydric phenols showed 96% destruction of phenolics, a 50% reduction in B.O.D. but a reduction in total organic carbon of only 22%.