Chlorine dioxide is a strong oxidizing gas that is highly explosive, and must be diluted with rare elemental gases as much as possible during production and use, and at the same time needs to be avoided from light, vibration or heating.
The sterilization, food preservation, deodorization effect of other chemicals can not be replaced, because they can not be transported to use the site production. Therefore, there is a chlorine dioxide generator. The principle of its production:
(1) sodium chlorate and concentrated hydrochloric acid reaction method (Kestiog method) At present, some European countries mainly use sodium chlorate (NaClO3) oxidation of concentrated hydrochloric acid preparation method, the chemical reaction equation is: 2NaClO3 + 4HCl (concentrated) = 2NaCl + Cl2 ↑ + 2ClO2 ↑ + 2H2O. the shortcomings of this method is mainly the simultaneous generation of a large amount of chlorine gas, not only to produce a large amount of chlorine gas, not only to use the field production. A large amount of chlorine gas is produced, not only the yield is low, but also the product is difficult to separate, and at the same time it is likely to cause environmental pollution. (2) Sodium chlorite and chlorine gas reaction method After scientific exploration, our scientists found a preparation method superior to that of Europe, which is made by passing chlorine gas diluted by dry air into the reaction column filled with solid sodium chlorite (NaClO2). The chemical reaction equation is: 2NaClO2 + Cl2 = 2NaCl + 2ClO2. This method is characterized by good safety, no toxic by-products. (3) oxalic acid reduction method Recently, scientists have studied a new preparation method, in acidic solution with oxalic acid (H2C2O4) reduction of sodium chlorate, the chemical reaction equation is: H2C2O4 + 2NaClO3 + H2SO4 = △ = Na2SO4 + 2CO2 ↑ + 2ClO2 ↑ + 2H2O and 2ClO3 + H2C2O4 = K2CO3 + CO2↑ + H2O and 2ClO3 + H2C2O4 = K2CO3 + CO2↑ + CO2 + 2ClO2↑ + H2O The most important feature of this method is that due to the dilution of carbon dioxide generated during the reaction process, it greatly improves the safety of production and storage and transportation. (4) sodium chlorite and hydrochloric acid reaction method At present, the commonly used method of preparing high-purity chlorine dioxide, the chemical reaction equation is: 5NaClO2 + 4HCl = 4ClO2 + 5NaCl + 2H2O, the product of this process in the purity of the product is generally up to 95% or more, the need for on-site preparation for on-site use. The use of high corrosion-resistant materials produced by the chlorine dioxide generator can meet the application. (5) potassium chlorate and sulfur dioxide reaction method Advantage is that sulfur dioxide can be used to reduce air pollution chemical reaction equation is: 2KClO3 + SO2 = 2ClO2 + K2SO4