Chlorine dioxide generating process
AssigneeSterling Canada, Inc.
InventorMarek Lipsztajn
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Abstract
Chlorine dioxide is produced by reaction of sodium chlorate, a reducing agent, preferably methanol or hydrogen peroxide, and sulfuric acid at the boiling point of the reaction medium under a subatmospheric pressure. Present in the reaction medium is a component which suppresses the solubility of by-product sodium sulfate and thereby increases the concentration of free hydrogen ions in the reaction medium available for reaction to form chlorine dioxide. The solubility-depressing component generally is an inert alkali metal salt, preferably an inert sodium salt, such as perchlorate or nitrate. By increasing the concentration of hydrogen ions available for reaction, it is possible to achieve an improvement in the rate of production of chlorine dioxide.
Claims20
In a process for the production of chlorine dioxide, which comprises reducing sodium chlorate with a reducing agent in an aqueous acid reaction medium containing sulfuric acid in a reaction zone, maintaining the reaction medium at its boiling point while a subatmospheric pressure is applied thereto, removing chlorine dioxide from the reaction zone in gaseous admixture with steam, depositing a by-product sodium sulfate in the reaction zone, and removing the deposited sodium sulfate from the reaction zone,
- the improvement which comprises:
- having present in the reaction medium at least one alkali metal salt which is inert in the reduction reaction before reducing the sodium chlorate.
Dependencies are inferred from the claim text.