On-line Measurement of Sub-ppb Level Hydrogen Peroxide in Ultrapure Water Production Process

Abstract

An on-line H O 2 analyzer was developed for application to the ultrapure water production process, using a gasometric method. The analyzer consists of a dissolved oxygen (DO) sensor and analyzer, a catalyst that converts H 2 O 2 to O 2 , and a computer that stores the DO data. H 2 O 2 concentrations were calculated by measuring the change in DO concentration before and after the catalyst and using the calculation formula presented in this study. In order to accurately analyze a sub-ppb level of H 2 O 2 , a DO meter which can correctly measure the DO concentration at the ppb level was applied. An ion exchange resin with Pd, was selected as an appropriate catalyst since it could decompose 99% of H 2 O 2 to O 2 at a space velocity of 120/h. The minimum analysis time was 20 min, and the detection limit was observed to be 0.27 ppb. When the DO concentration of the sample was 1.5 ppb or lower, an H 2 O 2 concentration of 1 ppb or lower was successfully measured. Good correlation, with an R 2 value of 0.99, was observed between the measured and calculated H 2 O 2 concentrations.

Chemiluminescent Measurement of Hydrogen Peroxide in the Exhaled Breath Condensate of Healthy and Asthmatic Adults

“…It was noted that the vehicle control still displayed luminescence emission above baseline and higher than the instrument blank. We hypothesized that this could be due to residual hydrogen peroxide in the water used to prepare stock solutions for hydrogen peroxide calibration . This was confirmed by performing a control experiment with the addition of 2 U mL –1 catalase, an enzyme that catalytically decomposes hydrogen peroxide (Figure B).…”