Abstract: In this paper, ozone water was prepared by directly dissolving ozone gas in water, and its concentration was measured by ultraviolet absorption method corrected by iodine stoichiometry titration method.By chemical kinetics method, the effects of water quality, temperature and pH value on the stability of ozone water were studied, and a preliminary approach about stabilizing ozone in aqueous solution with acetic acid, citric acid and so on was provided in this paper. The experimental results showed that water quality, temperature and pH value were important factors affecting the stability of ozone water. The better water quality was, the more stable ozone water was, and ozone decomposed very slowly in double-distilled water. Lowering water temperature could enhance the stability of ozone water. Ozone decomposed much quickly in alkaline solution, and its decomposition was heavily inhibited in acid solution, but excessive acidity could also accelerate ozone’s decay and reduce the stability of ozone water. Additionally, a little acetic acid or citric acid could greatly improve the stability of ozone water. As far as the effect was concerned, acetic acid was better than citric acid. Sodium chloride could hardly increase the stability of ozone water, and it accelerated ozone’s decay when a large amount was added.

Key words: Ozone water , Stability , Kinetics