Moisture-activated chlorine dioxide-releasing powder and method of manufacture
AssigneePhiex Technologies, Inc.
InventorsSumner Barenberg, Robert Cameron, Xiao Tian
Life of this patent
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Abstract
Methods of manufacturing a moisture-activated powder are provided which provide generation and release of chlorine dioxide without detectable amounts of any toxic by-products such as chlorine gas, chlorites, or chlorates. The powder need not be exposed to light before or during exposure of the powder to moisture or relative humidity to generate the gas. The powder can also be prepared under conditions that minimize or prevent decomposition or oxidation of sodium chlorite or premature moisture activation of the powder during the manufacturing process to maximize its activity.
Claims17
A method of making a moisture-activated powder for providing controlled release of chlorine dioxide, the method comprising:
- admixing sodium chlorite, a silicate, and water to form an aqueous suspension, the aqueous suspension including sodium chlorite of 85-99% purity;
- and
- spray-drying the aqueous suspension at an inlet temperature ranging from about 482 to about 537° C. (900 to 1000° F.) and an outlet temperature of not more than 143° C. (290° F.) to form silicate particles,
- admixing an inorganic acid-releasing agent, an anhydrous material, and water to form a colloidal suspension;
- admixing the silicate particles with the colloidal suspension to form a slurry;
- and
- spray-drying the slurry at an inlet temperature ranging from about 482 to about 537° C. (900 to 1000° F.) and an outlet temperature of not more than 143° C. (290° F.) to form the powder,
- wherein the powder is substantially free of water and capable of generating and releasing chlorine dioxide in an amount effective for disinfection, without release of detectable amounts of chlorine gas, chlorates and/or chlorites, after hydrolysis of the acid releasing agent and reaction of hydronium ions with chlorite.
Dependencies are inferred from the claim text.