Finishing treatment processes for micropollutant degradation at the outlet of WWTP: Bibliometric analysis and QSPR/QSAR modeling

Micropollutants are substances, both synthetic and natural, that are discharged into the environment from point and non-point sources, which typically come from wastewater treatment plants (WWTP), enter the environment with treated wastewater and may be harmful to ecosystems, wildlife, and human health. The conventional water treatment techniques find it challenging to degrade these compounds due to their high stability. Despite advanced water treatment methods, some compounds remain unremovable. The decontamination of water from non-biodegradable micropollutants has encountered obstacles, necessitating the development of advanced technologies for follow-up processing. In this review, we focus the micropollutant removal using adsorption and photocatalysis technologies, we present a bibliometric analysis on nano-adsorbents, photocatalysts, and photoelectrocatalysis (PEC) technology. The chemical and degradation pathway diversity of micropollutants in real wastewater, experimentally determining the effectiveness of micropollutant degradation is an expensive and complex process. We propose the use nanocatatlysts to understand the quantitative relationship between the structural characteristics of micropollutants and their degradability, such as quantitative structure-property/ activity relationship (QSPR/QSAR) models. E.g., phenolic compounds with different substituents, according to the multiple linear regression (MLR) equation of the QSPR model, the degradation of phenolic compounds is greatly influenced by electronic, hydrophobic, topological, and steric properties. These QSPR models underwent strict internal and external statistical validation procedures and were trained to accurately predict the experimental degradation rate constants of the test set. We explore the potential benefits and limitations of various technologies and models for use in water treatment facilities.