Organophosphorus Pesticides Degradation from wastewater

Description

Organophosphorus pesticides (OPPs) constitute a major class of agrochemicals extensively applied in modern agriculture and vector control programs due to their high biocidal efficacy. However, their widespread usage has resulted in frequent detection in aquatic environments via non-point sources such as agricultural runoff and point discharges including industrial effluents. Owing to their chemical stability at trace concentrations, hydrophobicity, and resistance to conventional biological treatment processes, OPPs persist in wastewater matrices, posing significant ecotoxicological and human health risks through inhibition of acetylcholinesterase activity. Consequently, the development and implementation of efficient removal strategies are imperative for safeguarding water quality and ecosystem integrity. This study systematically investigates the degradation of selected OPPs, specifically malathion and diazinon, employing advanced oxidation processes (AOPs) as a sustainable and high-efficiency treatment approach. Emphasis is placed on the mechanistic role of hydroxyl radicals (OH) as non-selective oxidants, along with the influence of catalytic systems and operational parameters on degradation kinetics and mineralization efficiency. Experimental evaluation of treatment techniques, including FeGAC/H2 O2 (Fenton-like systems), UV-assisted photolysis, and sonophotocatalytic processes, demonstrates their effectiveness in achieving substantial pesticide removal. The study further incorporates comprehensive analytical assessment using chemical oxygen demand (COD) reduction and gas chromatography–mass spectrometry (GC–MS) to elucidate degradation pathways and intermediate formation. Overall, the work provides a detailed techno-scientific framework for optimizing AOP-based treatment systems, offering critical insights for environmental engineers, researchers, and policymakers focused on advanced wastewater remediation technologies.