Pyrite Prepared By The Low-cost Efficient And Pollution-free Disinfectant Chlorine Dioxide Process

Chlorine dioxide is the optimum disinfectant to be used at present, which is called the fourth generation disinfectant from abroad. It is extensively applied to the aspects of disinfections, drinking water, hospital sewage, food antisepsis and retaining freshness. The medical application is also beginning studying and there are medical application reported. Chlorine dioxide is becoming the first disinfectant. The preparations of chlorine dioxide includes many methods, such as preparations using excess HC1 with ClO₃^-, reacting NaCl with ClO₃^- in a strong H₂SO₄ solon and preparing by methyl alcohol. The preparation using methyl alcohol is the optimized method at present. In the research of recent years, chlorine dioxide generator has been developed. But new method has never been reported. The article introduces a new process in preparation of chlorine dioxide by reducing sodium chlorate in acid aqueous solution with pyrite. On the basis of experiments ,the optimized condition are obtained: reacting temperature:30°C, the sodium chlorate concentration:3mol/L, the sulfuric acid concentration: 7mol/L,the surplus rate of pyrite: 5%. The rate of production is 90.31%. The rate of purity is 91.57%. The method using pyrite is proved to be practicable and the new device is devised. The ability of device is 200 kg, which is the basis on the industry. The product is stable chlorine dioxide.Chlorine dioxide is sensitive to light and heat. It will decompose, Cl₂O₆ is mainly got at low temperature, Cl₂ and O₂ are products at high temperature. By the experiment, we find that the quantity of ClO₂ has decreased by 25% in 56 days. It proves that the ClO₂ solution is unstable. The present chlorine dioxide products are mainly the stable ClO₂ aqueous solution and solid chlorine dioxide. The stable ClO₂ aqueous solution is widely used in practice, and the stable chlorine dioxide we referred usually is the stable ClO₂ aqueous solution. We use Na₂CO₃ and H₂O₂ as stabilizer and the proper proportion of stabilizer is 2:3(mol: mol). By the test, the stable chlorine dioxide meets the standardization.The process and results of the industrialized experiments has been researched, the effect of which is optimum. There are a detailed compare chlorine dioxide with the other three generation disinfectant and the perspectives of its future.