Abstract: Hypochlorite salts and substantially dehydrated acid-form cation exchange resin beads are combined at specified ratios within a porous enclosure such as a pouch or sachet. Hypochlorous acid solutions are produced on demand by introducing the mixture-containing pouch into a chemical excess of water. Spontaneous exchange reactions occur at room temperature within a few minutes to produce aqueous hypochlorous acid, while the cations from the hypochlorite salt are simultaneously sequestered by the resin beads. The resin beads remain contained within the original porous enclosure to allow mechanical isolation or separation from the resulting solution.