Source: {"pile_set_name": "USPTO Backgrounds"}

This invention is related to a simple, new and useful method whereby some or all of a specific indoor pollutant can be removed.
Conventional methods usually involve the adsorption of such pollutants onto activated surfaces such as charcoal, silica gel, alumina or other materials with large surface areas, (see R. E. Goddard & J. A. Coles Canadian Pat. No. 625,216 and J. W. Kasmark Jr., M. L. Dooley & A. H. Jones U.S. Pat. No. 4,227,904.
Another conventional method is to use a solution to react with the specific gas, (see M. A. Kise, Canadian Pat. No. 643,062).
Such methods are usually non-specific and quite expensive to produce and operate. In the case where aqueous solutions are used the air becomes saturated with water and higher humidity levels result. In the case of adsorption systems, the pollutant, usually present in trace quantities, must compete with oxygen, nitrogen, carbon dioxide and water in the air in order to be adsorbed to a significant extent. The adsorption is also temperature dependent and not always complete as far as the pollutant is concerned.