Photocatalytic Degradation of Polycyclic Aromatic Hydrocarbon in Soil

As a class of persistent organic pollutants, polycyclic aromatic hydrocarbons (PAHs) have been widely distributed in soil, which is highly stable, hydrophobic, cytotoxic and difficult to degrade. The PAHs are commonly produced from transportation, industrial production and waste incineration. In recent years, the increasingly serious pollution of PAHs in soil has become a great threat to soil ecology, food safety and public health. Hence, the treatment of PAHs contaminated soil is of great importance and urgently needed. Among numerous strategies for PAHs degradation, photocatalytic technology has attracted extensive attention due to its low energy consumption, facile operation and environmental friendliness. In this paper, the photocatalytic degradation mechanism and pathway of PAHs are overviewed, the current state of knowledge concerning photocatalytic remediation of PAHs contaminated soils is reviewed, and the impacts of different environmental factors on the degradation efficiency of photocatalysts are discussed. Furthermore, we summarize the challenges to apply photocatalytic technology in the field of PAHs contaminated soil remediation. Key words polycyclic aromatic hydrocarbons; photocatalysis; soil remediation; degradation mechanism; influence factor