Abstract: Durability of emissions catalysts in vehicular and other emissions control systems is significantly increased by positioning, prior to the catalyst-laden catalytic converter, at least one poison trap consisting of a low back pressure structure having a coating which reacts with non-metal or amphoteric oxides to form non-volatile reaction products.

Abstract: A canister, especially for two-cycle engines, having both noise reduction and pollutant treatment attributes in a single unit. To effectuate sound reduction the canister muffler has mounted within it several tubes randomly arranged in relation to one another. Thus, an emission stream is forced to frequently change directions, causing a baffling effect and a reduction in noise. Further, these tubes are coated with a catalytic substance to treat the emission stream and thus decrease undesired pollutants. The turbulent flow of the emission stream caused by the tubes also serves to increase the contact with the catalyst. Hence, a single canister is all that is necessary to both silence and treat the emission exhaust stream.