Real-Time Monitoring of the Atrazine Degradation by Liquid Chromatography and High-Resolution Mass Spectrometry: Effect of Fenton Process and Ultrasound Treatment

Abstract

High resolution mass spectrometry (HRMS) was coupled with ultra-high-performance liquid chromatography (uHPLC) to monitor atrazine (ATZ) degradation process of Fenton/ultrasound (US) treatment in real time. Samples were automatically taken through a peristaltic pump, and then analysed by HPLC-HRMS. The injection in the mass spectrometer was performed every 4 min for 2 h. ATZ and its degradation metabolites were sampled and identified. Online Fenton experiments in different equivalents of Fenton reagents, online US experiments with/without Fe2+ and offline Fenton experiments were conducted. Higher equivalents of Fenton reagents promoted the degradation rate of ATZ and the generation of the late-products such as Ammeline (AM). Besides, adding Fe2+ accelerated ATZ degradation in US treatment. In offline Fenton, the degradation rate of ATZ was higher than that of online Fenton, suggesting the offline samples were still reacting in the vial. The online analysis precisely controls the effect of reagents over time through automatic sampling and rapid detection, which greatly improves the measurement accuracy. The experimental set up proposed here both prevents the degradation of potentially unstable metabolites and provides a good way to track each metabolite.

Degradation of herbicide atrazine in water by high voltage electrical discharge in comparison with Fenton oxidation and ultrasound treatments

“…Here, the energy was directly injected into the atrazine aqueous solution through a plasma channel formed by HVED between two submersed electrodes. It was aimed at investigating the ability of the HVED system to degrade atrazine in aqueous solution; comparing the results with a chemical degradation technique (Fenton oxidation) and physical degradation technique (ultrasound); studying the effect of Fe 2+ on atrazine degradation; identifying atrazine degradation metabolites by high performance liquid chromatography coupled with high resolution mass spectrometry (HPLC-HRMS) analysis; 33 and proposing detailed mechanisms of atrazine degradation pathways based on the formation kinetics of atrazine degradation metabolites.…”