The removal of micro(nano)plastics (MNPs) is currently a hot topic within the scientific community. So far, the investigation into the application of advanced oxidation processes for the degradation of MNPs has been limited, as denoted by the publication date (2019 – 2023) of the main literature in the field. Likewise, the characterization of nanoplastics (NPs) supposes a challenge among the research field. In PlasticOX, the progress of NPs degradation was effectively monitored in terms of Total Organic Carbon, turbidity, and particle size reduction (TEM analysis), as well as by other relevant characterization tools. Moreover, the viability of the photo-Fenton process (UV/H2O2/Fe) carried out at ambient conditions was demonstrated for the removal of polystyrene (PS) NPs from water. Under optimized conditions, complete mineralization of PS NPs was achieved in less than an hour at ambient conditions, exhibiting superior performance compared to the photocatalytic processes reported in the existing literature. To the best of our knowledge, these are the first studies reporting complete and rapid degradation of NPs in water, under ambient conditions. Furthermore, a kinetic model, based on the size change of the particles along the treatment time, was developed to predict the performance of the photo-oxidative treatment. Remarkably, no other studies elucidated the kinetic behavior of NPs degradation.
Therefore, the results of PlasticOX present a substantial contribution to: i) the scientific community, enhancing understanding in the fields of plastic pollution and wastewater treatment; ii) the wastewater treatment industry, especially companies focusing on commercializing photo-assisted treatment processes or the removal of micro(nano)plastics from water. Also, the companies operating municipal WWTPs seeking to incorporate advanced treatments as additional stages of their conventional installations, and iii) the general society, as one of the project’s main objectives was to raise awareness of environmental issues related to plastic pollution.