Patent ID: 8574605

Claim:
A method of preparing a bromine- and chlorine-containing liquid, comprising: (a) combining solid sulfamic acid, water, and a first alkaline source to form a solution of the salt of sulfamic acid, wherein said alkaline source is selected from the group consisting of alkali metal hydroxide and earth alkali metal hydroxide; (b) adding elemental bromine to said solution; (c) adding a solid organic chlorinating agent to said solution; (d) conducting a solid-liquid separation; (e) adding a second alkaline source, wherein said alkaline source is selected from the group consisting of alkali metal hydroxide and earth alkali metal hydroxide; and (f) forming a bromine- and chlorine-containing liquid, wherein the amounts of said solid sulfamic acid, water, first and second alkaline sources, and elemental bromine are such that said bromine- and chlorine-containing liquid has an active ingredient concentration of greater than 18% expressed as bromine or 8% expressed as chlorine, and further, wherein said bromine- and chlorine-containing liquid has a mole ratio of said sulfamic acid to available halogen provided by said elemental bromine added in step (b) and said solid organic chlorinating agent added in step (c) of between about 0.95:1 and about 1.2:1.