Continuous determination of hydrogen peroxide formed in advanced oxidation and electrochemical processes

Abstract

A hydrogen peroxide (H₂O₂) auto-analyzer was developed to continuously detect H₂O₂ present in water, using a flow injection analysis (FIA) technique, during several advanced oxidation processes (AOPs) involving H₂O₂, such as ozone/H₂O₂, UV/H₂O₂, and ozone/UV, and an electrochemical process. The analytical method was based on a fluorometric method, using the reaction of p-hydroxyphenyl acetic acid and H₂O₂ in the presence of peroxidase enzyme. H₂O₂ was analyzed within the high (100–2,000 μg/L) and low (0–500 μg/L) concentration ranges, using both long and short reaction coils, respectively. The standard deviation and detection limit were 0.5 and 1.6 μg/L, respectively, and the coefficient of variation at 1 μg/L was 7.8%. This study also investigated the effects of Na₂S₂O₃ and NH₄Cl, which were used to quench the ozone and hypochlorous acid (HOCl) present in the samples, on the measurement of H₂O₂ during the ozone-based AOPs and electrochemical process.

Keywords:

• Hydrogen peroxide auto-analyzer
• Flow injection analysis
• Advanced oxidation process

Acknowledgements

This subject is supported by the Korean Ministry of Environment as “The Eco-Innovation project (Global-Top project)” and Korea Institute of Construction Technology (KICT) as “Smart Water μ-Grid project”.

Notes

The 4th International Desalination Workshop (IDW4), 16–18 November 2011, Jeju Island, South Korea