Recent advances on photocatalytic degradation of phthalate ester plasticizers using nanomaterial photocatalysts

Phthalate esters (PAEs) are a class of organic ester compounds containing benzene rings, which have been widely applied as additives in various fields, especially as plasticizers in plastic product to improve the flexibility. Due to the non-covalent bonding, PAEs inevitably leach out from the plastic polymers into environments. PAEs are endocrine disruptors, which possess seriously hazards to organisms, such as reproductive and genetic abnormalities. Now, PAEs pollution has become a serious environmental problem. Moreover, due to its difficulty in natural degradation, it has become a widespread concern to eliminate PAEs pollution with energy-saving technology. Among various degradation technologies for organic pollutant removal, photocatalytic degradation has attracted more attentions due to the merits of low energy consumption, high removal efficiency, abundant photocatalyst and low secondary pollution. In this article, the photocatalytic degradation using nanomaterial photocatalysts towards four kinds of typical PAEs were reviewed, including di(2-ethylhexyl) phthalate (DEHP), dibutyl phthalate (DBP), dimethyl phthalate (DMP), and diethyl phthalate (DEP). To improve the photocatalytic degradation efficiency, various semiconductor photocatalysts have been developed, and the optical and electrochemical properties, and the degradation mechanism and pathway have been also discussed. Finally, the challenges and perspectives of photocatalytic technology on PAEs elimination were presented.