Oxidative degradation of phenols and substituted phenols in the water and atmosphere: a review

As a class of toxic compounds, phenols are difficult to biodegrade and will exist in the environment for a long time, posing potential risks to the environment and human beings. To avoid threatening the water environment and air quality, phenolic pollutants need to be treated effectively. This paper reviews the data concerning the environmental degradation of phenols and substituted phenols, both in the water and in the air. The values are respectively obtained from the experimental and theoretical researches. In wastewater, several advanced oxidation processes (AOPs) based on powerful transitory species which can efficiently degrade phenolic compounds were summarized. In terms of the atmospheric oxidative degradation, the reaction of phenols and substituted phenols with oxidants such as hydroxyl radical (•OH), nitrate radical (•NO3), Cl atoms, and ozone is probably a major degradation mechanism. The atmospheric degradation regular patterns of phenolic compounds initiated by different oxidants were also concluded.Graphic abstract