Process for removing nitrogen oxides from gaseous mixtures
AssigneeHodogaya Chemical Co., Ltd.
InventorsHiroyuki Yoshida, Katumi Saga
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Abstract
A process for removing nitrogen oxides including nitrogen monoxide from a gaseous mixture such as industrial waste gases is provided. The gaseous mixture is contacted, first, with an aqueous solution of a chlorate and, then, with water, an aqueous solution or dispersion of a basic compound or an aqueous alkaline solution or dispersion of a reducing agent.
Claims7
A process for removing nitrogen oxides from a waste gas containing the nitrogen oxides and sulfur dioxide which comprises the step of contacting said waste gas, first, at a temperature from room temperature to 80.degree. C with an aqueous acid solution consisting essentially of at least one chlorate selected from the group consisting of sodium chlorate, potassium chlorate, ammonium chlorate, calcium chlorate and barium chlorate and 1 to 80% by weight of an inorganic acid, selected from the group consisting of nitric acid, sulfuric acid and hydrochloric acid and then, with a liquid selected from the group consisting of an aqueous solution or dispersion of a basic compound and an aqueous alkaline solution or dispersion of at least one compound selected from the group consisting of alkali metal sulfides, alkali metal sulfites and hydrogen peroxide.
Dependencies are inferred from the claim text.