Methods and systems are provided for diagnosing a heating element coupled to a canister of an evaporative emissions control (EVAP) system. In one example, a method (or system) may include evacuating the canister at different temperature conditions, and diagnosing the heating element based on the different times taken to evacuate the canister at the different temperature conditions.

A graphene based adsorbent material incorporated into a scrubber forming a portion of a canister or connected to a vent port of the canister in the evaporative emissions management system. The adsorbent material is specifically adsorptive of vaporized hydrocarbons for preventing bleed emissions while also providing low flow restrictions. The graphene adsorbent being provided as an activated graphene derivative and a polymer extruded in a honeycomb design pattern to provide a plurality of passageways for the flow of the vapors. The scrubber connected to the EVAP canister vent port and incorporating a scrubber element exhibiting a honeycomb extruded structure having any combination of activated graphene-derivatives, lignocellulose, charcoal, ceramic, binder and flux material.

An evaporative emission control canister system comprises an initial adsorbent volume having an effective incremental adsorption capacity at 25° C. of greater than 35 grams n-butane/L between vapor concentration of 5 vol% and 50 vol% n-butane, and at least one subsequent adsorbent volume having an effective incremental adsorption capacity at 25° C. of less than 35 grams n-butane/L between vapor concentration of 5 vol% and 50 vol% n-butane, an effective butane working capacity (BWC) of less than 3 g/dL, and a g-total BWC of between 2 grams and 6 grams. The evaporative emission control canister system has a two-day diurnal breathing loss (DBL) emissions of no more than 20 mg at no more than 210 liters of purge applied after the 40 g/hr butane loading step.

An evaporative emission control canister system comprises an initial adsorbent volume having an effective incremental adsorption capacity at 25° C. of greater than 35 grams n-butane/L between vapor concentration of 5 vol % and 50 vol % n-butane, and at least one subsequent adsorbent volume having an effective incremental adsorption capacity at 25° C. of less than 35 grams n-butane/L between vapor concentration of 5 vol % and 50 vol % n-butane. The evaporative emission control canister system has a two-day diurnal breathing loss (DBL) emissions of no more than 20 mg at no more than 210 liters of purge applied after the 40 g/hr BETP butane loading step.

The present description provides high working capacity adsorbents with low DBL bleed emission performance properties that allows the design of evaporative fuel emission control systems that are lower cost, simpler and more compact than those possible by prior art. Emission control canister systems comprising the adsorbent material demonstrate a relatively high gasoline working capacity, and low emissions.

A vehicle canister device includes a main canister including an inlet port through which evaporative gas is introduced from a fuel tank, an outlet port through which the evaporative gas introduced during operation of an engine is discharged to an intake side of the engine, and an internal space for filling activated carbon. The vehicle canister device also includes an auxiliary canister mounted in fluid-communication with the main canister and configured to allow external air to flow into the main canister through an atmosphere port provided on the main canister or the evaporative gas to flow therethrough upon stop of the engine. The auxiliary canister includes a plurality of activated carbon layers each filled with an activated carbon and a plurality of air layers disposed between the activated carbon layers.

Provided is a canister that makes it possible to reduce production costs. One aspect of the present disclosure is a canister. The canister includes an outer case including a charge port that takes in an evaporated fuel, a purge port that discharges the evaporated fuel, and an atmosphere port open to the atmosphere, an inner case arranged inside the outer case, the inner case having an inner space to which the atmosphere port is connected, a first adsorption chamber arranged in the inner space of the inner case, and a second adsorption chamber arranged between the first adsorption chamber and the atmosphere port in a flow path of the evaporated fuel in the inner space of the inner case. A cross-sectional area perpendicular to a gas flow direction in the second adsorption chamber and a cross-sectional area perpendicular to a gas flow direction in the first adsorption chamber are different.

The present disclosure relates to hydrocarbon emission control systems. More specifically, the present disclosure relates to substrates coated with hydrocarbon adsorptive coating compositions and evaporative emission control systems for controlling evaporative emissions of hydrocarbons from motor vehicle engines and fuel systems. The hydrocarbon adsorptive coating compositions include particulate carbon having a BET surface area of at least about 1300 m.sup.2/g, and at least one of (i) a butane affinity of greater than 60% at 5% butane; (ii) a butane affinity of greater than 35% at 0.5% butane; (iii) a micropore volume greater than about 0.2 ml/g and a mesopore volume greater than about 0.5 ml/g.

Methods and systems are provided for carrying out diagnostics of a bleed canister of an evaporative emissions control system in a vehicle. In one example, a method may include, loading the bleed canister during a refueling event, and then during an immediately subsequent engine start, detecting if the bleed canister is degraded or not based on output of an exhaust gas oxygen sensor.

An activated carbon filter for reducing hydrocarbon emissions, includes a plurality of channels, the channels being suitable for the flow of gases therethrough and at least part of the surface of the channel walls having activated carbon for absorbing and/or adsorbing substances, in particular hydrocarbons; and a filter peripheral wall on the outer periphery of the activated carbon filter; wherein the filter peripheral wall includes a barrier layer, in particular in the form of a coating on the outer surface of the filter peripheral wall, preventing or at least significantly reducing the penetration, in particular the diffusion, of gases and/or substances, in particular hydrocarbon-containing gases, through the filter peripheral wall.