Analysis of Functional Water —An Environmentally Friendly Analytical Method Using an Alkaline Chloride Aqueous Solution—

Abstract

As functional water, a dilute aqueous solution of alkali chloride was taken up. Analysis of electrolyzed water produced by electrolysis, and separation/concentration system using water above the eutectic point and below 0 °C were introduced. Electrolyzed water has a bactericidal effect due to the action of generated hypochlorous acid, but it has been shown that active oxygen other than hypochlorous acid is involved in the bactericidal action. It was also found that KCl contributes more to active oxygen than NaCl due to the influence of the alkali metal ions of the salt used as an electrolysis aid. A further investigation of suitable preparation methods for the application is required. We are developing a system that can separate and concentrate inorganic cations and small organic molecules by keeping the aqueous solution of alkali chloride at –10°C, which is higher than the eutectic point of alkali chloride and water and lower than the melting point of water. We are proceeding with a further research as an environmentally friendly analytical method that does not use harmful chemical substances.