Selective removal of contaminants of emerging concern (CECs) from urban water cycle via Molecularly Imprinted Polymers (MIPs): potential of upscaling and enabling reclaimed water reuse

Contaminants of emerging concern (CECs) are one of the main barriers in the water cycle as they limit the water reuse due to their adverse effects on humans and the ecosystem. Natural and/or engineered ecosystems, such as conventional wastewater treatment processes, are not designed to remove CECs and contribute to the bioaccumulation in organisms considering high volumes of treated water discharges. The adoption of innovative solutions to upgrade urban water cycle facilities has gained relevance for the removal of these substances from final effluents. Molecularly imprinted polymers (MIPs) show promising selective removal toward a wide range of CECs. However, this process is still limited to lab/bench scale and needs to be critically analyzed and assessed for possible scale-up in real environment. Therefore, in this review, an overview of the fate and occurrence of CECs in wastewater is initially reported together with the state-of-the-art adsorption mechanisms to remove these compounds. In the central part of the paper, an evaluation of MIPs synthesis and their status in removing CECs from water matrix are presented. An upscaling pathway of MIPs column from lab- to pilot-scale is given to be applied for enhanced CECs removal and safe water reuse in irrigation/fertigation. Finally, possible integration of MIP columns to real wastewater treatment facilities is discussed and advantages and disadvantages of the potential solutions are addressed to enhance their sustainability.