A more selective and accurate method than indigo method for measuring dissolved ozone concentration (p-vinylbenzoic...

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Water Treatment Technologies

Background:

• Accurate dissolved ozone concentration measurement is vital for effective ozone treatment processes.
• Conventional indigo method for ozone measurement is susceptible to interference from other water constituents reacting with C-C double bonds.

Purpose of the Study:

• To develop a novel, interference-free method for measuring dissolved ozone concentration.
• To establish a more reliable and accurate alternative to the conventional indigo method for ozone monitoring.

Main Methods:

• Developed a new method measuring p-formylbenzoic acid (p-FBA) produced from the reaction of p-vinylbenzoic acid and ozone.
• Validated the method's specificity against common interfering substances like hypochlorous acid and hydrogen peroxide.
• Utilized liquid chromatography with ultraviolet and mass spectrometric detection for p-FBA analysis.

Main Results:

• The new method demonstrated high specificity, with p-FBA formation minimally affected by other oxidants.
• A consistent yield of p-FBA to ozone was observed across river water, treated wastewater, and seawater.
• The developed method exhibited smaller experimental errors compared to the indigo method and does not require complex calibration.

Conclusions:

• The novel p-FBA method provides a robust and accurate approach for dissolved ozone concentration measurement.
• This technique offers significant advantages over the indigo method, including enhanced specificity, reduced calibration needs, and suitability for simultaneous analysis.
• The new method supports improved ozone treatment efficacy and advanced ozonation management strategies.