2023 Volume 72 Issue 1.2 Pages 25-32
The shortage and pollution of drinking water are becoming severe problems in many parts of the world. Sanitary water supply is a vital issue for human life. For water disinfection, it is essential to control the concentration of free and combined chlorine appropriately. The authors constructed a flow injection analysis (FIA) system to simultaneously determine free and combined chlorine based on the difference in the photolysis reaction rate. The proposed system contained a Y-branch to separate the injected sample solution into light-irradiated and non-light-irradiated channels. The signals derived from the sample solution, divided into these channels, were detected individually with a time difference, and the simultaneous determination with a single sample injection became available. This study demonstrated the simultaneous determination of hypochlorite ion and chloramine T in the mixture using a pair of simultaneous equations based on pre-prepared relationship curves. The analytical results obtained by the proposed system coincided with the added amount in the mix.
