Abstract: A low-resistance hydrocarbon adsorber comprising a spiral-wound laminated structure for mounting into an entrance port of an engine air intake system to prevent hydrocarbon evaporations from reaching atmosphere. Preferably, the adsorber is formed as a cartridge and comprises a flexible polymeric sheet support to which a thin flexible sheet of activated carbon sheeting is laminated on a first support side. The support is provided on a second side with features, for example, ribs or bumps, extending above the surface. When the laminate is spirally wound, the spiral convolutions are spaced apart by the features. Preferably, the convolutions are spaced apart by a distance such that there is a high probability that hydrocarbons migrating out of a shut down engine will encounter the adsorber and thus be adsorbed before reaching the atmosphere. The windings may fill all or a portion of the open area of the intake port.

Abstract: A low-resistance hydrocarbon-adsorptive cartridge for an air intake of an internal combustion engine comprising a structure for being mounted into a portion of an engine air intake system. The structure is adapted to orient and retain one or more thin sheets of activated carbon sheeting in the intake system. Preferably, a plurality of sheets is oriented such that the leading edge of each sheet is presented to the engine intake air stream, thereby minimizing reduction in total cross-sectional area of the intake system. Preferably, the one or more sheets are spaced apart by a distance that is small relative to the extent of the elements in the direction of engine air flow such that a high probability is created that hydrocarbons migrating out of a shut down engine's intake manifold will encounter a surface of at least one of the adsorptive sheets and thus be adsorbed.