Abstract:

To discuss the dynamic variation of potassium ferrite (K2FeO4) on oxidation-reduction potential (Oxidation- Reduction Potential, ORP) and its acute toxicology to fish; the experiment measured the dose, time, and pH depended-ORP of K2FeO4, and its acute toxicology to carp (Cyprinus carpio), tilapia (Oreochromis aureus), and zebra fish (Brochydaino rerio). The results showed that, ORP in aquatic environment positively depended on the concentration of K2FeO4 when it was dissolved into aquatic environment. ORP in aquatic environment decreased to the minimum concentration and reached to steady state after 48 h. The effect of pH to ORP was also very evident; the details showed that the decrease rate in alkaline water was higher than that one in acidity and neutral water. Different fish had different toxicology to K2FeO4, the 96 h LC50 to carp, tilapia fish, zebra fish was 156.36, 145.31, 123.74 mg/L respectively, and the toxic effect occurred before 48 hours, and disappeared in 48-96 h. The experiment showed that the toxic effect to fish directly depended on the ORP of K2FeO4 in aquatic environment, the toxic effect of K2FeO4 to fish was caused by the strong oxidizing property.