Preparation method of sodium chlorite

Abstract

The invention discloses a preparation method of sodium chlorite. The preparation method comprises the following steps of (1) enabling sodium chlorate solution to react with hydrochloric acid to generate chlorine dioxide gas and chlorine; (2) leading chlorine dioxide gas and chlorine into sodium chlorite solution to further react, so as to generate chlorine dioxide gas; (3) leading the chlorine dioxide gas into sodium hydroxide solution, and adding hydrogen peroxide to react, so as to generate sodium chlorite at the same time; (4) crystallizing and drying sodium chlorite prepared in the step (3) to obtain a final product, wherein the concentration of the sodium chlorate solution in the step (1) is 25-33%, the concentration of hydrochloric acid solution in the step (1) is 31%, and the molar ratio of the hydrochloric acid to chlorous acid in the step (1) is (1-1.5) to 2. The preparation method of sodium chlorite disclosed by the invention does not utilize concentrated sulfuric acid of which the concentration is over 95%, is easy in control of the reaction process, not drastic in reaction, higher in safety coefficient, low in cost, and suitable for industrial large-scale application at the same time.

Description

technical field [0001] The invention relates to a preparation method of sodium chlorite for industrial bleaching. Background technique [0002] Sodium chlorite is an oxidant widely used in bleaching, environmental disinfection and other industries. The current production process is to react saturated sodium chlorate solution with 27.5% hydrogen peroxide and 95% sulfuric acid to generate chlorine dioxide gas, and then Chlorine gas is passed into the mixed solution of hydrogen peroxide and sodium hydroxide to react to form sodium chlorite. Since the reaction process uses more than 95% concentrated sulfuric acid, the reaction process is violent, easy to cause danger, and the cost is high, so it is not suitable for industrial application. . Contents of the invention [0003] Main purpose of the present invention is to overcome the defective that the preparation method of existing sodium chlorite exists, and provide a kind of preparation method of novel sodium chlo...

AI Technical Summary

Problems solved by technology

[0002] Sodium chlorite is an oxidizing agent widely used in bleaching, environmental disinfection and other industries. The current production process is to react saturated sodium chlorate solution with 27.5% hydrogen peroxide and 95% sulfuric acid to generate chlorine dioxide gas, and then Chlorine gas is passed into the mixed solution of hydrogen peroxide and sodium hydroxide to react to form sodium chlorite. Since the reaction process uses more than 95% concentrated sulfuric acid, the reaction process is violent, easy to cause danger, and the cost is high, so it is not suitable for industrial application.