Compositions and methods for storing aqueous chlorine dioxide solutions

Abstract

The present invention is directed to both physical and chemical means for maintaining continuous high levels of chlorine dioxide in aqueous solutions for extended periods, with minimum loss through degradation in the solution and dissipation through the walls of the containing vessel within which the solution is stored. The ClO2 may be maintained even in the absence of very high levels of chlorite, from which supplemental, offsetting levels of ClO2 may be generated. The present invention relates to the discovery that certain types of plastic and glass containers have the ability to maintain relatively constant levels of ClO2 in their contained solutions over extended periods, particularly in aqueous compositions comprising chlorite/ClO2 ratios sufficient for a stabilizing complex of the two, presumably Cl204—, to suppress the ClO2 loss. Of particular value is certain high-density polyethylene terephthalate (PETE) plastic bottling and plastic containers which have been initially exposed to a fluorinating environment. Specifically, in the latter regard, it has been discovered that certain plastic containers which ordinarily are incapable of maintaining aqueous ClO2 levels can be treated with fluorine gas to transform their surfaces so as to effectively suppress ClO2 diffusion therethrough.

Dependencies are inferred from the claim text.