A human oral care composition, includes safe and effective amounts of the fluoride ion and stabilized chlorine dioxide, that may take the form of a paste, gel, rinse, spray, powder, varnish or similar that reduces demineralization and promotes remineralization of teeth. The method includes the topical application of the composition to the human oral cavity (including but not limited to the teeth, gingiva, and tongue), preferably at least once daily, to enhance the anti-caries effect of fluoride by released chlorine dioxide compromising any biofilm present.

Compositions and methods for generating ClO.sub.2 gas are disclosed. A composition that includes a chlorite salt is activated by exposure to ultraviolet light. After an optional storage period, the composition is then exposed to moisture, resulting in the generation of ClO.sub.2 gas. Exemplary compositions include polymers in which the chlorite salt is dispersed. The polymers may be used to form films that can be used to package, e.g., food products, pharmaceutical products, medical devices, and/or laboratory devices. Upon exposure to ultraviolet light and moisture, the packaging releases controlled quantities of ClO.sub.2 gas, which may disinfect and/or deodorize the packaged device or product.

Provided is a chlorine dioxide generation device, suitable for long-term storage, discharging a chlorine dioxide-generating mixture that remains at an object of interest when used to thereby stably exhibit the effect of chlorine dioxide. A chlorine dioxide generation device, comprising: a first container containing a first composition comprising a chlorite and fumed silica; a second container containing a second composition comprising an acidic substance and fumed silica; an outer container housing the first container and the second container; a mixing section that mixes the first composition released from the first container and the second composition released from the second container to produce a mixed composition; and a discharging section that discharges the mixed composition produced by mixing in the mixing section.

A chlorine dioxide gas generator (100) is provided which capable of efficiently generating and gasifying a chlorine dioxide solution within a short period of time without accidental leakage, facilitating fumigation, and facilitating washing of the interior of the generator within a short period of time. The chlorine dioxide gas generator (100) includes a separation tank (20) that separates a chlorine dioxide gas (30b) from a chlorine dioxide solution (30a) generated in the reactor (10), the separation tank (20) including a separation cylinder (21), downwardly convex trays (22), upwardly convex tray covers (23), nubs (24) packed between the trays (22) and tray covers (23), a liquid supply pipe (25) communicating with an upper portion of the separation cylinder (21), and an air-mixture cylinder (27) that forms an air-mixture space (27a) around the separation cylinder (21) on a waste liquid chamber (26).

A method for boosting the efficiency of chlorine dioxide production in a chemical facility. A chloride donor is introduced into a feed of sulfuric acid or a reducing agent, both of which are injected into the recirculation lines, or other areas, of a chlorine dioxide producing facility. The chloride donor provides the intermediate chemical species necessary for the efficient generation of chlorine dioxide at high acidities and/or the high local acidity in the wake zone of the acid injection location, thereby enabling greater efficiency in the reduction of chlorine dioxide from sodium chlorate.

This invention relates to aqueous solutions that contain chlorine dioxide, particularly ultrapure aqueous solutions of chlorine dioxide that can be used, for example, in the field of human and veterinary medicine to disinfect surfaces, devices and instruments, as well as a process for producing such aqueous solutions of chlorine dioxide. In particular, this invention is a process for producing an aqueous solution of chlorine dioxide in which a previously produced aqueous solution of chlorine dioxide is treated so that an ultrapure aqueous solution of chlorine dioxide is obtained. The invented process can be applied to all previously produced aqueous solutions of chlorine dioxide, regardless of the process used to produce these. The invented process can be used in particular to produce ultrapure aqueous solutions of chlorine dioxide much more easily and inexpensively from previously produced aqueous solutions of chlorine dioxide. Surprisingly, it was discovered that the aqueous solutions of chlorine dioxide produced using the invented process show a high level of purity and a surprisingly high level of stability.

A composition for generating chlorine dioxide comprises active ingredients, a suitable hydrophobic compound, and a suitable super absorbent compound. A suitable hydrophobic compound will, among other characteristics, repel the solvent for at least the initial 30 seconds of exposure thereto. A suitable super absorbent compound will, among other characteristics, absorb at least 75 times its weight in solvent and will not gel until the chlorine-dioxide generating reaction is substantially complete.

An apparatus for preparing aqueous chlorine dioxide solutions is described, comprising (a) a reactor (1), (b) a first reservoir unit (8) comprising a first reactant for preparation of chlorine dioxide, the first reactant being in solid form, having an inlet (15) for water and a separate outlet (21), the first reservoir unit (8) being exchangeable, (c) a second reservoir unit (4) for storing a second reactant for preparation of chlorine dioxide. Additionally described are an exchangeable reservoir unit for such an apparatus, a kit comprising or consisting of one or more exchangeable reservoir units and a process for preparing a chlorine dioxide-containing solution usable directly for water treatment.

Preparation of an aqueous chlorine dioxide solution that reaches a first chlorine dioxide concentration during a first time period, and reaches a terminal concentration thereafter. A dilute solution of aqueous sodium chlorite or chlorate with predetermined concentration is produced, which yields the terminal chlorine dioxide concentration once an acid activator is added. The dilute solution is transferred through a conduit into a sanitization zone. The acid activator is injected into the conduit at a rate and concentration selected to reach the first chlorine dioxide concentration at the end of the first time period, with a flow rate such that the activated dilute solution of aqueous sodium chlorite has passed through the conduit prior to reaching the first chlorine dioxide concentration, which thereby limits exposure of the conduit to levels less than the first chlorine dioxide concentration.

A gaseous species can be separated from an aqueous donor mixture and absorbed in an aqueous recipient mixture using a membrane separation apparatus while maintaining a large temperature difference (e.g. greater than 30° C.) between the two aqueous mixtures. A composite membrane is employed which comprises a non-porous membrane adjacent a porous membrane. The non-porous membrane is permeable to the gaseous species. The porous membrane has a porosity greater than 50% and is hydrophobic. In one embodiment, the composite membrane is oriented such that the porous membrane faces the aqueous recipient mixture and is impermeable thereto at the recipient mixture pressure. The invention is particularly suitable for separating chlorine dioxide from chlorine dioxide reaction liquor and absorbing in chilled water.