Light-activated chlorine dioxide-releasing powder
AssigneePhiex Technologies, Inc.
InventorsSumner Barenberg, Robert Cameron, Xiao Tian
Life of this patent
Estimating the term…
Abstract
Methods of manufacturing a light-activated powder are provided which provide solid-state 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 moisture, relative humidity, or an acid before or during exposure of the powder to visible light to generate the gas. The powder can also be prepared under conditions that minimize or prevent decomposition or oxidation of sodium chlorite or premature light activation of the powder during the manufacturing process to maximize its activity.
Claims22
-23. (canceled)
A light-activated powder comprising about 50 wt. % to about 99.99 wt. % of a photocatalyst, and about 0.01 wt. % to about 50 wt. % sodium chlorite of 85-99% purity, wherein:
- the light-activated powder does not include sources of moisture that could initiate chlorine dioxide release;
- when exposed to light, the light-activated powder is capable of generating the solid-state controlled release of chlorine dioxide from the powder in an amount effective for disinfection, without release of detectable amounts of chlorine gas, chlorates and/or chlorites;
- and
- the light-activated powder being prepared by a method comprising:
- admixing the photocatalyst, a base, the sodium chlorite, and water to form an aqueous suspension;
- and
- spray-drying the 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 the light-activated powder, wherein the admixing and spray-drying steps are performed in darkness.
Dependencies are inferred from the claim text.