The effect of dissolved humic acid on the oxidation of phenolic endocrine disrupting chemicals (EDCs) by potassium permanganate was studied. It was found that the degradation of phenolic EDCs is promoted to various extents by the addition of humic acid. Results show that the removal rate of estrone by permanganate within 3 min of reaction time is increased from approximately 10% in control experiments to 68% when 0.08 mg l−1 of humic acid is present in the reaction system. The oxidation experiment of nine types of phenolic EDC by permanganate confirms that the promotion induced by the addition of humic acid varies in the cases of different EDCS. Results also indicate that the promotion induced by the presence of humic acid takes effect under acidic and neutral pH conditions, while the effect of pH plays a dominant role for the degradation of phenolic EDCs under alkaline conditions. Additionally, it was found that the oxidation of estrone by permanganate is promoted through the addition of humic acid to natural waters.
Keywords: humic acid, permanganate, pH, phenolic endocrine disrupting chemicals