TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Composition: The coating contains an acidic or basic reactant. The absorbant particle is carbon, ion-exchange media or zeolite.Preferred Performance: The absorber is fed with a gas stream containing at least 1000 ppm of contaminant and removes at least 90%, preferably at least 98%, of this contaminant. Preferably the absorber is fed with a gas stream containing 2 ppb to 50 ppm-volume of contaminant and removes at least 99% of this contaminant at a pressure not more than 1, preferably not more than 0.5, inches water at an airflow filter face velocity of 0.5 m/s.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Composition: The coating contains an acidic or basic reactant.Preferred Performance: The absorber is fed with a gas stream containing at least 1000 ppm of contaminant and removes at least 90%, preferably at least 98%, of this contaminant. Preferably the absorber is fed with a gas stream containing 2 ppb to 50 ppm-volume of contaminant and removes at least 99% of this contaminant at a pressure not more than 1, preferably not more than 0.1, inch water at an airflow filter face velocity of 0.5 m/s..Preferred Contaminant: The removed contaminant comprises a volatile organic compound, preferably gasoline, diesel or a silane compound, an acidic and/or basic component.    TECHNOLOGY FOCUS - CHEMICAL ENGINEERING - Preferred Construction: The passages have a honeycomb, preferably hexagonal or rectangular, cross-sectional shape. The wall thickness not more than 0.1 mm. The exposed surface area defined by the passages is 250 cm2-10 m2. The absorber thickness/passage length is 2-10 cm. The cross-sectional width of each passage is 0.5-2 mm. The passages define an inlet and outlet of the absorber and there is a particulate filter attached to the inlet. At least three absorber elements are used, the first comprising an acidic reactant and the second a basic reactant. The surface area of the faces of the absorber are 77.5-155 cm2.Preferred Method: After contaminant has been removed a further step of removing the contaminant from the coating is used, preferably by the application of heat and air flow through the absorber.    TECHNOLOGY FOCUS - POLYMERS - Preferred Binder: The polymer binder is poly-(2-hydroxyethyl methacrylate), polyethylene glycol or polyvinyl acetate.Preferred Composition: The absorbant particle is ion-exchange media.