Low-emission absorbent and canister system

Abstract

To provide a low-emission absorbent and a canister system.SOLUTION: This invention provides low DBL bleed emission performance properties that allow the design of evaporative fuel emission control systems that are simpler and more compact than those possible by prior art by inclusion of a vent-side volume comprising a parallel passage adsorbent such as a carbon honeycomb with narrow channel width and low cell pitch.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority to earlier-filed U.S. Provisional Patent Application No. 63 / 001,164, entitled "Low Emission Adsorbent and Canister System," filed March 27, 2020, and U.S. Provisional Patent Application No. 63 / 111,768, entitled "Low Emission Adsorbent and Canister System," filed November 10, 2020, both of which are incorporated by reference in their entireties herein.

[0002] The present disclosure, in various embodiments, relates generally to evaporative emissions control systems. [Background technology]

[0003] Evaporation of gasoline fuel from an automobile's fuel system is a major potential source of hydrocarbon air pollution. These fuel vapor emissions occur while the vehicle is running, refueling, or parked (i.e., the engine is off). Such emissions can be controlled by a canister system that uses activated carbon to adsorb fuel vapors emitted from the fuel system. During certain engine operating modes, the adsorbed fuel vapors are periodically removed from the activated carbon by purging the canister system with ambient air to desorb the fuel vapors from the activated carbon. The regenerated carbon is then ready to adsorb additional fuel vapors.

[0004] It is well known in the art that more space-efficient activated carbon adsorbents for this concentration swing application are characterized by n-butane vapor adsorption isotherms with steep adsorption capacities toward high vapor partial pressures (U.S. Pat. No. 6,540,815). Thus, the adsorbents have high capacities at relatively high concentrations of the types of vapors present in gasoline fuels, and the adsorbents facilitate the release of these trapped vapors when exposed to low vapor concentrations or partial pressures, such as during purging. These high performance activated carbons have a large amount of pore volume as "small mesopores" (e.g., SAE Technical Papers 902119 and 2001-03-0733, and Burchell 1999, pp. 252-253), which are preferably about 1.8 nm to about 5 nm in size, as measured by the Barrett, Joyner and Halenda (BJH) method of analysis of nitrogen adsorption isotherms (e.g., U.S. Pat. No. 5,204,310). (According to the IUPAC classification, small mesopores are pores of about 1.8-2 nm size in the <2 nm micropore size range and about 2-5 nm size in the 2-50 nm mesopore size range.) Small mesopores are small enough to capture vapor as a condensed phase, but are easily emptied when exposed to low partial pressures of vapor. Thus, the volume within these pores correlates linearly with the recoverable vapor capacity of the adsorbent within the canister volume, known as the gasoline working capacity (GWC), which in turn correlates linearly with the ASTM butane working capacity (herein, "ASTM BWC") of the adsorbent, as measured by standard ASTM 5228 method, which is incorporated herein by reference. Commercially available activated carbon products for this application have an ASTM BWC range of about 3 to about 17 g / dL, with 9+ g / dL BWC carbons being suitable for the working volume toward the fuel vapor source in a canister system and one or more subsequent volumes toward the atmospheric port or vent side (i.e., the vent-side adsorbent volume) for lower BWC carbons. Generally, cylindrical pellets and other engineered shapes (e.g., spherical granules) of activated carbon are preferred over irregularly shaped or crushed particulates, especially in canister systems where moderate flow restriction is required, for example, for vapor capture during refueling.Advantages of pelletized and engineered activated carbon include excellent mechanical strength, low dust, low particulate generation, high on-size yield during processing, and narrow particle size distribution that provides consistency throughout liter-sized canister fills after bulk shipping and handling.

[0005] Although highly mesoporous adsorbents are preferred for their working capacity, the high ASTM BWC of the adsorbent and its high GWC actually appear to be at odds with the concurrent need for fuel vapor emission control systems to provide low emissions even when the vehicle is not running.

[0006] For example, growing environmental concerns continue to drive stricter regulations of hydrocarbon emissions. When a vehicle is parked in a warm environment during the day (i.e., daytime warming), the temperature in the fuel tank increases, resulting in an increase in vapor pressure in the fuel tank. Typically, to prevent fuel vapors from escaping from the vehicle to the atmosphere, the fuel tank is vented through a conduit to a canister containing a suitable fuel adsorbent material capable of temporarily adsorbing fuel vapors. The canister defines a vapor or fluid flow path such that when the vehicle is stationary, fluid fuel vapors pass from the fuel tank through the fuel tank conduit, through one or more adsorbent volumes, and out a vent port open to the atmosphere. A mixture of fuel vapor and air from the fuel tank enters the canister through the fuel vapor inlet of the canister and diffuses into the adsorbent volume where the fuel vapors are adsorbed in a temporary storage area, and the purified air is released to the atmosphere through the vent port of the canister. When the engine is running, ambient air is drawn into the canister system through the vent port of the canister. Purge air flows through the sorbent volume in the canister and desorbs the fuel vapors adsorbed in the sorbent volume before entering the internal combustion engine through a fuel vapor purge conduit. The purge air does not desorb all of the fuel vapors adsorbed in the sorbent volume, resulting in residual hydrocarbons (a "heel") that may be released to the atmosphere.

[0007] Additionally, the heel, being in local equilibrium with the vapor phase, also allows fuel vapors from the fuel tank to migrate through the canister system as emissions. Such emissions typically occur when a vehicle is parked and subject to diurnal temperature variations over a period of several days, and are commonly referred to as "diurnal breathing loss" (DBL) emissions. California's low-emission vehicle regulations require that these DBL emissions from canister systems be less than 10 mg for most 2003 model year and newer vehicles ("PZEV"), and less than 50 mg for most 2004 model year and newer vehicles, and typically less than 20 mg ("LEV-II").

[0008] Currently, California's Low Emission Vehicle ("LEV-III") and Federal Tier 3 standards mandate that canister DBL emissions not exceed 20 mg per the Bleed Emissions Test Procedure (BETP), as described in California Evaporative Emissions Standards and Test Procedures for 2001 and Subsequent Model Motor Vehicles, March 22, 2012. Additionally, regulations regarding DBL emissions continue to pose challenges to evaporative emission control systems, especially when purge air levels are low. For example, the potential for DBL emissions may be more severe for hybrid vehicles, including vehicles whose powertrains are both internal combustion engines and electric motors ("HEVs"), and vehicles that have an idle-stop system that automatically shuts down and restarts the internal combustion engine to reduce the time the engine spends idling, thereby reducing fuel consumption and tailpipe emissions. In such hybrid vehicles, the internal combustion engine may be shut off for nearly half of the time during vehicle operation. Because the fuel vapors adsorbed in the adsorber are purged only when the internal combustion engine is running, the adsorber in the canister of a hybrid vehicle is purged with fresh air in less than half the time compared to a conventional vehicle, often within the range of 55 Bed Volumes (BV) to 100 BV (based on the U.S. EPA Federal Test Procedure (FTP)-75 drive cycle), where "BV" is the ratio of the total purge flow rate to the volume of the adsorber in the canister system. Nevertheless, hybrid vehicles generate nearly the same amount of evaporated fuel vapors as conventional vehicles. The low purge frequency and low purge volume of a hybrid vehicle may be insufficient to remove residual hydrocarbon heels from the adsorber in the canister, resulting in higher DBL emissions. Other powertrains are similarly challenged to provide high levels of purge to refresh the canister and provide the optimal mixture and speed for the engine when designed for optimal driving performance, fuel efficiency, and tailpipe emissions.These powertrains include turbocharged or turbo-assisted engines, and gasoline direct injection ("GDI") engines.

[0009] In contrast, globally, evaporative emissions regulations have been less stringent than in the United States, but there is now a trend toward more stringent regulations along the path taken by the United States. There is growing awareness of the benefits of better use of vehicle fuels and stricter controls for cleaner air, especially in areas where the use of light-duty vehicles is growing rapidly and air quality issues require urgent attention. As a notable example, the Ministry of Environmental Protection of the People's Republic of China issued regulations in 2016 that include limits on fuel vapor emissions, to be implemented in 2020 (see Limits and Measurement Methods for Emissions from Light-Duty Vehicles, GB 18352.6-2016, also known as "China 6"). This standard specifies limits and measurement methods, technical requirements, and durability measurement methods for pollution prevention devices for light-duty vehicles, including hybrid electric vehicles with forced ignition engines for exhaust gas emissions at normal and low temperatures, real driving emissions (RDE), crankcase emissions, evaporative emissions and refueling emissions, as well as on-board diagnostic systems (OBD).

[0010] While the test protocols and emissions limits for whole vehicle testing are specified in the regulations, there is leeway for vehicle manufacturers to allocate design limits for components that contribute to total emissions (e.g., evaporative emission control canister systems, fuel tank walls, hoses, tubes, etc.). Of the allocations, the limits for evaporative emission control canister systems are generally set during the fuel system and vehicle design process to have worst-case day DBL emissions of less than 100 mg as part of the design balance to meet the overall vehicle requirements of the China 6 regulations.

[0011] To meet evaporative fuel emission standards during the vehicle design phase, vehicle manufacturers typically provide potential suppliers with target specifications for the overall canister system performance in terms of functional content, appearance, physical properties, and durability, thus leaving the canister system manufacturer with suitable design flexibility to achieve these goals. For example, General Motors Corporation sets many design specifications for evaporative emission control canister systems (see GMW16494). A notable specification is the total allowable pressure drop for carbon canister systems. In this example, the maximum flow limit for a canister system intended for on-board on-board vapor recovery (ORVR) "shall be 0.90 ± 0.225 kPa at an air flow rate of 60 liters per minute (lpm) when measured at the tank tube with air flowing from the canister tank tube to the fresh air tube" (see section 3.2.1.3.2.2 of GMW-16494). This specification and others in GMW-16494 provide examples of the extent to which vehicle manufacturers are permitted to limit flow.

[0012] As a result of such specifications, canister system designers appreciate a variety of chamber design and adsorbent selection options, as requirements vary widely for various vehicle platforms from various vehicle manufacturers according to engine type, engine operating design, space availability, purge availability, and canister system control policies, in addition to various fuel emission regulations around the world. Indeed, "one size does not fit all" for the design of the canister system and its adsorbent loading.

[0013] Several methods have been reported to meet the apparently conflicting needs of high working capacity and low DBL emission performance. One method is to significantly increase the volume of the purge gas to promote desorption of the residual hydrocarbon heel from the adsorption volume; see U.S. Pat. No. 4,894,072. However, this method has the disadvantage of complicating management of the fuel / air mixture to the engine during the purge step, tends to adversely affect tailpipe emissions, and such high levels of purging are not available in certain powertrain designs. At the expense of design and installation, auxiliary pumps can be used at certain locations within the evaporative emission control system to supplement, assist, or increase the purge flow rate or volume as a means of supplementing engine suction and avoiding some of the problems with engine performance and tailpipe emission control when relying solely on engine suction.

[0014] Another method is to design the canister so that the cross-sectional area on the vent side of the canister is relatively small, either by resizing the existing canister or by installing a suitably sized auxiliary vent side canister. This method reduces the residual hydrocarbon heel by increasing the strength of the purge air. One drawback of such an approach is that the relatively small cross-sectional area places excessive flow restrictions on the canister system. See U.S. Patent No. 5,957,114.

[0015] Another method to increase purge efficiency is to heat the purge air and / or a portion of the adsorbent volume that adsorbs the fuel vapors. However, this method adds complexity to the control system management and raises some safety concerns. See U.S. Patents 6,098,601 and 6,279,548.

[0016] Another method is to route the fuel vapor through a fuel-side adsorbent volume located near the fuel source in the fluid stream and through at least one subsequent (i.e., vent-side) adsorbent volume located downstream of the fuel-side adsorber, prior to release to the atmosphere, where the fuel-side adsorbent volume (here, the initial adsorbent volume) has a greater slope of the isotherm, defined as the incremental adsorption capacity, than the subsequent (i.e., vent-side) adsorbent volume. See U.S. Reissue Patent No. 38,844, which is incorporated herein by reference in its entirety.

[0017] Another method that is particularly useful when only low levels of purging are available is to route the fuel vapor through at least one subsequent (i.e., vent-side) adsorber that has incremental adsorption capacity, volume-average ASTM BWC, specific g-total BWC capacity, and / or substantially uniform configuration of openings that facilitate nearly uniform air and vapor flow distribution throughout its flow cross-section (see U.S. Patent Nos. 9,732,649 and 10,960,342, which are incorporated herein by reference in their entireties).

[0018] One effective type of trailing adsorbent volume with less incremental adsorption capacity toward the vent side of the canister system is an elongated cylindrical ceramic-bonded activated carbon honeycomb, such as Nuchar® HCA or HCA-LBE (Ingevity®, North Charleston, South Carolina, USA), typically available in diameters of 29, 35, and 41 mm, and specific lengths ranging from 50 to 200 mm. The internal parallel passage structure is a square grid of about 200 cells per square inch (cpsi), with cell wall thicknesses of about 0.3 mm. These engineered parts are expensive to manufacture and require specialized skills and equipment to fabricate. Care must be taken to precisely control the raw material properties, formulation, mixing, extrusion, heat treatment, and cutting to meet final product specifications for mechanical strength, adsorption capacity, and flow restrictions. The finished adsorbent parts must be durable, defect-free, dimensionally accurate, and function for emission control for virtually the entire life of the vehicle. These ceramic bonded honeycombs are very effective as vent-side adsorbent volume packings for controlling diurnal breathing loss emissions, but some fuel systems require larger sized components and multiple components in series to achieve the emissions control goals. Nevertheless, at very low purge levels, honeycombs may not be able to achieve the emission control goals, resulting in the use of very expensive closed tank fuel systems.

[0019] Therefore, there is a strong need for new adsorber options and methods to balance the tradeoffs in terms of cost, size, flow limitations, working capacity, diurnal breathing loss (DBL) performance, complexity, and deployment flexibility. For example, it would be desirable to have a higher performance adsorber honeycomb that allows for a smaller, less complex approach to system design and operation, both when normal or low levels of purge are available. Summary of the Invention

[0020] Adsorbent materials in the form of parallel path adsorbent volumes (PPAVs), evaporative emission control canister systems, and methods of use thereof, configured to provide surprisingly and unexpectedly low DBL bleed emissions performance characteristics when incorporated into a vehicle exhaust canister system are now described. The described PPAVs advantageously allow for the design of simpler, more compact evaporative fuel emission control systems than currently known or available systems. As described herein, the evaporative emission control canister systems comprising the PPAVs described herein have demonstrated very low emissions when tested under standard vapor cycling protocols using standard bleed emissions test procedures, e.g., California Evaporative Emissions Standards and Test Procedures for 2001, and BETP as written in Subsequent Model Motor Vehicles, March 22, 2012. [Means for solving the problem]

[0021] Thus, in one aspect, the present specification provides a PPAV comprising an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface, the parallel passages or channels having a mean channel hydraulic diameter (herein, “t c,Dh "), hydraulic diameter cell pitch of less than 1.5 mm (herein "CP Dh "), or combinations thereof. When incorporated into an evaporative emissions system as detailed herein, the PPAVs described herein surprisingly and unexpectedly provide reduced DBL bleed emissions while providing a simpler design.

[0022] In another aspect, the present specification provides an evaporative emission control canister system comprising one or more canisters comprising a fuel-side adsorbent volume and at least one vent-side parallel passage adsorbent volume (PPAV), the at least one vent-side PPAV comprising an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface, the parallel passages or channels having a mean channel hydraulic diameter (t) of 1.25 mm or less. c,Dh ), hydraulic diameter cell pitch (CP Dh ), or combinations thereof. In another aspect or embodiment described herein, the present disclosure provides an evaporative emission control system comprising a fuel tank for storing a fuel, an engine comprising an air induction system and adapted to consume the fuel, and one or more canisters comprising a fuel-side sorbent volume and at least one vent-side PPAV, the at least one vent-side PPAV comprising an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface, the parallel passages or channels having a mean channel hydraulic diameter (t) of 1.25 mm or less. c,Dh ), hydraulic diameter cell pitch (CP Dh ), or a combination thereof; a fuel vapor inlet conduit connecting the evaporative emission control canister system to a fuel tank; a fuel vapor purge outlet conduit connecting the evaporative emission control canister system to an air induction system of the engine; and a vent conduit for venting the evaporative emission control canister system to atmosphere and for inputting purge air to the evaporative emission control canister system, the vent conduit being formed by a fuel vapor flow path from the fuel vapor inlet conduit to the at least one PPAV to the fuel side adsorbent volume and to the vent conduit, and by an air flow path from the vent conduit to the at least one PPAV to the fuel side adsorbent volume and to the fuel vapor purge outlet.

[0023] In any of the aspects or embodiments described herein, the evaporative emission control canister system has a two-day diurnal breathing loss (DBL) of 50 mg or less with a purge of 315 liters or less, or 150 bed volumes or less applied after a 40 g / hr butane fill step as measured by the 2012 California Bleed Emissions Test Procedure (BETP).

[0024] In any of the aspects or embodiments described herein, the PPAV comprises an adsorbent material selected from the group consisting of activated carbon, carbonized charcoal, zeolites, clays, porous polymers, porous alumina, porous silica, molecular sieves, kaolin, titania, ceria, metal organic frameworks, and combinations thereof.

[0025] In any of the aspects or embodiments described herein, the formed PPAV adsorbent material comprises activated carbon derived from a material comprising a member selected from the group consisting of wood, wood dust, wood flour, cotton linters, peat, coal, coconut, lignite, carbohydrates, petroleum pitch, petroleum coke, coal tar pitch, fruit pits, fruit stones, nut shells, nut pits, sawdust, palm, vegetables, synthetic polymers, natural polymers, lignocellulosic materials, or combinations thereof. In any of the aspects or embodiments described herein, the formed PPAV adsorbent material comprises activated carbon derived from at least one of wood, wood dust, wood flour, cotton linters, peat, coal, coconut, lignite, carbohydrates, petroleum pitch, petroleum coke, coal tar pitch, fruit pits, fruit stones, nut shells, nut pits, sawdust, palm, vegetables, or combinations thereof.

[0026] In any of the embodiments described herein, the evaporative emissions control system may further include a heating unit.

[0027] In another aspect, the present specification provides a method for reducing fuel vapor emissions in an evaporative emission control system, the method including contacting fuel vapors with an evaporative emission control system described herein comprising a PPAV described herein.

[0028] The foregoing general description of utility is presented for illustrative purposes only and is not intended to limit the scope of the disclosure and the appended claims. Other objects and advantages associated with the compositions, methods, and processes of the present invention will be apparent to those skilled in the art in view of the claims, detailed description, and examples of the present invention. For example, the various aspects and embodiments of the present invention can be used in many combinations, all of which are expressly contemplated by this specification. Such additional advantages, objects, and embodiments are expressly included within the scope of the present invention. Publications and other materials used to describe the background of the invention and, in certain cases, to provide additional details regarding the implementation are incorporated by reference.

[0029] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate several embodiments of the present invention and, together with the description, serve to explain the principles of the invention. The drawings are only for the purpose of illustrating embodiments of the invention and are not to be construed as limiting the invention. Further objects, features and advantages of the present invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings showing exemplary embodiments of the invention. [Brief description of the drawings]

[0030] [Figure 1] FIG. 1 is a cross-sectional view of an exemplary evaporative emission control canister system (100) described herein. [Diagram 2] FIG. 2 is a cross-sectional view of an exemplary evaporative emission control canister system (100) described herein. [Diagram 3]FIG. 3 is a cross-sectional view of an exemplary evaporative emission control canister system (100) described herein that includes a main canister with four adsorbent volumes (201, 202, 203, and 204) and an auxiliary canister (300) with a subsequent adsorbent volume (301) therein. [Figure 4] FIG. 4 is a cross-sectional view of an exemplary evaporative emission control canister system (100) described herein that includes a main canister with four adsorbent volumes (201, 202, 203, and 204) and an auxiliary canister (300) with two subsequent adsorbent volumes (301, 302) therein. [Diagram 5] FIG. 5 is a cross-sectional view of an exemplary evaporative emissions control canister system (100) illustrating the system in which the DBL emissions performance of comparative and inventive examples was measured, with three adsorbent volumes (501, 203, 204) in the main canister, when a single PPAV honeycomb (502) is present in the auxiliary vent canister (300). [Figure 6] FIG. 6 is a cross-sectional view of an exemplary evaporative emission control canister system (100) illustrating the system on which the DBL emissions performance of comparative and inventive examples was measured when there were only two adsorbent volumes (501, 202) in the main canister and one PPAV honeycomb (502) in the auxiliary vent canister (300). [Figure 7] FIG. 7 is a cross-sectional view of an exemplary evaporative emissions control canister system (100) illustrating the system on which the DBL emissions performance of comparative and inventive examples was measured when there are only two adsorbent volumes (501, 202) in the main canister and two PPAV honeycombs (502, 504) in an in-line auxiliary vent canister (300, 503). [Figure 8]FIG. 8 is a cross-sectional view of an exemplary evaporative emissions control canister system (100) illustrating the system in which the DBL emissions performance of comparative and inventive examples was measured, where there are three adsorbent volumes (501, 203, 204) in one portion of the main canister and two PPAV honeycombs (502, 504) in series in another portion of the canister. [Figure 9] FIG. 9 illustrates the cross-sectional morphology of a honeycomb-based PPAV described herein and illustrates the cell wall thickness (tw), channel width (tc), channel area (Ac), channel perimeter (Pc), and outer wall thickness (ts) of an exemplary honeycomb-shaped PPAV described herein. [Figure 10] FIG. 10 illustrates four rotations in which the outer diameter (Do) of an exemplary honeycomb-shaped PPAV is measured with both caliper and image analysis measurements. [Figure 11] FIG. 11 illustrates four rotations in which the inner diameter (Di) of an exemplary honeycomb-shaped PPAV is measured by image analysis measurements. [Figure 12] FIG. 12 illustrates vertical and horizontal crosshairs where the mid-channel width and wall thickness (tc,m and tw,m) and base channel width and wall thickness (tc,b and tw,b) are obtained by image analysis of an exemplary honeycomb-shaped PPAV. [Figure 13] FIG. 13 illustrates an n×n (“n×n”) square cell grid, with the n×n grid channel width (tc,nxn) and n×n wall thickness (tc,m and tw,nxn) obtained by image analysis of an exemplary honeycomb-shaped PPAV. [Figure 14] Figure 14 is a plot of the effluent concentration response of unused PPAV during initial saturation from a dynamic butane adsorption capacity test. Efficiency is the cumulative adsorbed mass fraction (shaded area) relative to the cumulative inlet mass up to the saturation point (e.g., 95%). [Figure 15]Figure 15 shows the effluent concentration response of the PPAV with recycle during the saturation step after the first saturation and purge step from the dynamic butane adsorption capacity test. In the case of the PPAV with recycle of the previous adsorption and purge, there is also MTZ breakthrough. In addition, residual heel from incomplete adsorbate removal from the previous purge step leads to bleed-through of the adsorbate in the effluent before MTZ breakthrough. [Figure 16] FIG. 16 is a graph of the effluent concentration response characteristics of PPAV recycled during the saturation step after the initial saturation and purge steps, using a dynamic butane adsorption capacity test for an intermediate breakthrough point of 25% for an inlet butane concentration of 0.5 vol.%. [Figure 17] FIG. 17 shows day 2 DBL emissions as a function of PPAV mean channel hydraulic diameter (tc,Dh) for a 35 mm diameter by 150 mm long comparative example (open circles) and an inventive example (closed circles) test data. [Figure 18] FIG. 18 shows test data for a comparison of 35 mm diameter by 150 mm length DBL emissions on day 2 as a function of PPAV channel hydraulic diameter cell pitch (CPDh) (open circles) and an example of the invention (closed circles). [Figure 19] FIG. 19 shows test data for 2-day DBL emissions as a function of (tc, average) for several PPAV channel widths for a 35 mm diameter by 150 mm long comparative example (open circles) and an embodiment of the invention (closed circles). [Figure 20] FIG. 20 shows test data for 2-day DBL emission as a function of PPAV cell pitch based on multiple channel widths (CPtc, average, i.e., “multiple cell pitch widths”) for a 35 mm diameter by 150 mm long comparative example (open circles) and an example of the invention (filled circles). [Figure 21] FIG. 21 shows test data for 2-day DBL emissions as a function of PPAV cell density (cells per square inch, cpsi) for a 35 mm diameter by 150 mm long comparative example (open circles) and an example of the invention (closed circles). [Figure 22]FIG. 22 shows test data for 35 mm diameter by 150 mm long comparative (open circles) and inventive examples (closed circles) of DBL emissions at day 2 as a function of PPAV cell wall thickness (tw, average). [Figure 23] FIG. 23 shows test data for macropore ratio (M / M and M / m) as a function of cell density (cells per square inch, cpsi) for 35 mm diameter by 150 mm long comparative examples (open circles and open squares) and examples of the invention (filled circles and filled squares). [Figure 24] FIG. 24 shows test data for macropore volume (PV) as a function of cell density (cells per square inch, cpsi) for 35 mm diameter by 150 mm long comparative examples (open circles and open squares) and examples of the invention (closed circles and closed squares). [Diagram 25] FIG. 25 presents test data for 35 mm diameter by 150 mm length comparative (open circles) and inventive example (closed circles) DBL emissions on day 2 as a function of PPAV flow restriction (kPa) at 40 lpm. [Figure 26] FIG. 26 shows day 2 DBL emissions as a function of PPAV mean channel hydraulic diameter (tc,Dh) for a 35 mm diameter by 150 mm long comparative example (open circles) and an inventive example (closed circles) test data. [Figure 27] FIG. 27 shows test data for day 2 DBL emissions as a function of PPAV cell density (cells per square inch, cpsi) for a 29 mm diameter by 150 mm long comparative example (open diamonds) and an example of the invention (closed diamonds), as well as a PPAV with slit-shaped cells (closed rectangles). [Figure 28] FIG. 28 shows test data for day 2 DBL emissions as a function of PPAV cell pitch based on hydraulic diameter (CPDh) for a 29 mm diameter by 150 mm length comparative example (open diamonds) and an example of the invention (closed diamonds), as well as a PPAV with slit-shaped cells (closed rectangles). [Figure 29]FIG. 29 shows test data for day 2 DBL emission as a function of PPAV cell pitch based on multiple channel widths (CPtc, average) or PPAV cell pitch based on narrow channel widths based on the cell pitch of the slit-shaped cell embodiment for a 29 mm diameter by 150 mm long comparative example (white diamonds) and embodiment of the invention (black diamonds), and a PPAV with a slit-shaped cell (black rectangle). [Diagram 30] FIG. 30 presents test data for comparative examples (open circles) and inventive examples (closed circles) of DBL emissions on day 2 as a function of BWC (g / dL) of PPAV. [Diagram 31] FIG. 31 shows test data for comparative (open circles) and inventive examples (closed circles) of DBL emissions on day 2 as a function of PPAV IAC (g / L-bed). [Diagram 32] FIG. 32 presents test data for the comparative example (open circles) and the inventive example (closed circles) of DBL emissions on day 2 as a function of purge volume in liters (L). [Diagram 33] FIG. 33 provides test data for comparative examples (open circles) and inventive examples (closed circles) of DBL emissions on day 2 as a function of bed volume purge (BV). [Diagram 34] FIG. 34 presents test data for the comparative example (open circles) and the inventive example (closed circles) of DBL emissions on day 2 as a function of purge volume in liters (L). [Diagram 35] FIG. 35 provides test data for comparative examples (open circles) and inventive examples (closed circles) of DBL emissions on day 2 as a function of bed volume purge (BV). [Diagram 36] FIG. 36 presents test data for the virgin fraction adsorption efficiency (DAEV95%) as a function of cell density (cells per square inch, cpsi) for comparative examples (open circles) and examples of the present invention (closed circles). [Figure 37] FIG. 37 provides test data for the virgin fraction adsorption efficiency (DAEV95%) as a function of cell pitch based on hydraulic diameter (CPDh) for comparative examples (open circles) and examples of the present invention (closed circles). [Figure 38] FIG. 38 presents test data for the circulating fraction adsorption efficiency (DAEC 95%) as a function of cell density (cells per square inch, cpsi) for comparative examples (open circles) and examples of the present invention (closed circles). [Figure 39] FIG. 39 shows test data for the circulation fraction adsorption efficiency (DAEC 95%) as a function of cell pitch based on hydraulic diameter (CPDh) for comparative examples (open circles) and examples of the present invention (closed circles). [Diagram 40] FIG. 40 shows test data for the circulating fraction adsorption efficiency (DAEC 0.125 vol%) as a function of cell density (cells per square inch, cpsi) for comparative examples (open circles) and examples of the invention (closed circles). [Diagram 41] FIG. 41 shows test data for the adsorption efficiency of the circulation portion (DAEC 0.125 vol%) as a function of cell pitch based on hydraulic diameter (CPDh) for comparative examples (open circles) and examples of the present invention (closed circles). [Diagram 42] FIG. 42 shows test data for 35 mm diameter by 150 mm length comparative (open circles) and inventive example (closed circles) DBL emissions on day 2 as a function of PPAV mass of bleed-through before 5% BT. [Diagram 43] FIG. 43 shows test data for a 35 mm diameter by 150 mm length comparative example (open circles) and an inventive example (closed circles) of DBL emissions on day 2 as a function of percent PPAV entering as bleed-through relative to total butane delivered before 95% BT. [Diagram 44] FIG. 44 presents test data for 35 mm diameter by 150 mm length comparative (open circles) and inventive example (closed circles) DBL emissions on day 2 as a function of PPAV bleed-through relative to total adsorbed mass before 95% BT. [Diagram 45] FIG. 45 provides test data for gasoline working capacity as a function of PPAV cell density (cells per square inch, cpsi) for 35 mm diameter by 150 mm long comparative examples (open circles) and examples of the invention (closed circles). [Figure 46]FIG. 46 is a diagram of the x and y axis directions applied to image analysis of a PPAV portion having slit-shaped cells. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] Hereinafter, the present disclosure will be described in more detail, although not all embodiments of the present disclosure are shown. Although the present disclosure has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes can be made and elements thereof can be replaced with equivalents without departing from the scope of the present disclosure. Furthermore, many modifications can be made to adapt a particular structure or material to the teachings of the present disclosure without departing from the essential scope of the present disclosure.

[0032] When a range of values ​​is provided, it is understood that each value between the upper and lower limits of that range and any other stated range, as well as any value within that stated range, is included in the invention. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges, which are also encompassed within the invention, as are any specifically excluded limits in the stated range. When the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention.

[0033] The following terms are used to describe the present invention. If a term is not specifically defined herein, the term is given its art-recognized meaning by those of ordinary skill in the art who apply the term in the context of its use in describing the present invention.

[0034] As used herein, the articles "a" and "an" are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article, unless the context clearly indicates otherwise. By way of example, "an element" means one element or more than one element.

[0035] As used herein in the specification and claims, the term "and / or" should be understood to mean "either or both" of the elements so conjoined. That is, in some instances the elements are conjointly present and in other instances they are non-conjoined. Multiple elements listed with "and / or" should be interpreted in the same manner, that is, "one or more" of the elements are so conjoined. Other elements other than the elements specifically identified by the "and / or" clause may optionally be present, whether related or not to those specifically identified elements. Thus, as a non-limiting example, when used in conjunction with open-ended language such as "comprising," a reference to "A and / or B" may, in one embodiment, refer only to A (optionally including elements other than B); in another embodiment, it may refer only to B (optionally including elements other than A); in yet another embodiment, it may refer to both A and B (optionally including other elements); and so forth.

[0036] As used herein in the specification and claims, "or" should be understood to have the same meaning as "and / or" as defined above. For example, when separating items in a list, "or" or "and / or" shall be interpreted as inclusive, i.e., including at least one of, but also including a plurality of, a number or list of elements, and optionally including additional items not listed. Only terms clearly indicating the contrary, such as "only one of," or "exactly one of," or, when used in the claims, "consisting of," shall refer to the inclusion of exactly one element of a number or list of elements. Generally, as used herein, the term "or" should be interpreted to indicate exclusive alternatives (i.e., "one or the other, but not both") only when preceded by an exclusive term, such as "either," "one of," "only one of," or "exactly one of."

[0037] In the claims, as well as in the above specification, all transitional phrases such as "comprising," "including," "carrying," "having," "containing," "involving," "holding," "composed of," and the like, are to be understood to be open-ended, i.e., to mean inclusive but not limited to. The transitional phrases "consisting of" and "consisting essentially of" alone are intended to be closed and semi-closed transitional phrases, respectively, as set forth in Section 2111.03 of the 10 United States Patent Office Manual of Patent Examining Procedures.

[0038] As used herein, in the specification and claims, the phrase "at least one" in reference to a list of one or more elements should be understood to mean at least one element selected from any one or more of the elements in the list of elements, but not necessarily including at least one of all the elements specifically listed in the list of elements, and not excluding any combination of the elements in the list of elements. Furthermore, this definition allows for the optional presence of elements other than those specifically identified in the list of elements to which the phrase "at least one" refers, whether or not related to those specifically identified elements. Thus, as a non-limiting example, "at least one of A and B (or, equivalently, "at least one of A or B" or, equivalently, "at least one of A and / or B") can refer, in one embodiment, to at least one, optionally including a plurality of A, with no B (and optionally including elements other than B); in another embodiment, to at least one, optionally including a plurality of B, with no A (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including a plurality of A, and at least one, optionally including a plurality of B (and optionally including other elements). etc. It should also be understood that, unless expressly stated otherwise, in any method claimed herein that includes one or more steps or actions, the order of the steps or actions of the method is not necessarily limited to the order of the steps or actions of the method recited.

[0039] As used herein, the phrases "less than" (e.g., less than about 2) or "less than or equal to" (e.g., about 2 or less) followed by a number refer to a non-zero number that is less than the recited number, or a non-zero number that is less than or equal to the recited number, respectively.

[0040] As used herein, the terms "fluid," "gas" or "gaseous" and "vapor" or "vaporous" are used in a generic sense and are intended to be interchangeable unless the context clearly indicates otherwise.

[0041] Described herein is an evaporative emission control canister system comprising a parallel passage adsorbent volume (PPAV) article (herein "molded PPAV" or "PPAV"), and which exhibits surprisingly and unexpectedly reduced diurnal breathing loss (DBL) emissions as a result of the PPAV being located on the vent side of the system. As used herein, unless the context clearly indicates otherwise, a PPAV refers to an individual article or component (i.e., nominal volume), which includes an adsorbent material and has an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface, the parallel passages or channels being configured as described herein.

[0042] Thus, in one aspect, the present disclosure provides a PPAV comprising an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface, the parallel passages or channels having a mean channel hydraulic diameter (t c、Dh ), hydraulic diameter cell pitch (CP) less than 1.5 mm Dh ), or combinations thereof. When incorporated into an evaporative emissions system as detailed herein, the PPAVs described herein surprisingly and unexpectedly provide reduced DBL bleed emissions while providing a simpler design.

[0043] In any aspect or embodiment described herein, the 4ΣA c / ΣP c The average channel hydraulic diameter of the PPAV (t c,Dh) is, for example, 1.25 mm or less, 1.20 mm or less, 1.10 mm or less, 1.0 mm or less, or about 0.01 mm to about 1.25 mm, about 0.1 mm to about 1.25 mm, about 0.2 mm to about 1.25 mm, about 0.3 mm to about 1.25 mm, about 0.4 mm to about 1.25 mm, or about 0.1 mm to about 1.20 mm, about 0.1 mm to about 1.15 mm, about 0.1 mm to about 1.10 mm, about 0.1 mm to about 1.0 mm, about 0.2 mm to about 1.20 mm, about 0.2 mm to about 1.15 mm, about 0.2 mm to about 1.1 mm, and about 0.4 mm to about 1.0 mm, about 0.4 mm to about 1.25 mm, about 0.4 mm to about 1.20 mm, about 0.4 mm to about 1.15 mm, about 0.4 mm to about 1.1 mm, about 0.4 mm to about 1.0 mm, about 0.4 mm to about 0.95, or about 0.4 mm to about 0.9 mm, and including all subranges and combinations thereof.

[0044] In any aspect or embodiment described herein, the mean channel hydraulic diameter (t c,Dh ) and average wall thickness (t w,平均 ) is calculated by the sum of the hydraulic diameter of the PPAV and the cell pitch (CP Dh ) is, for example, less than 1.50 mm, less than 1.40 mm, or less than 1.30 mm, or about 0.5 mm to about 1.5 mm, or about 0.5 mm to about 1.4 mm, or about 0.5 mm to about 1.3 mm, or about 0.5 mm to about 1.2 mm, or about 0.6 mm to about 1.5 mm, or about 0.6 mm to about 1.4 mm, or about 0.6 mm to about 1.3 mm, or about 0.6 mm to about 1.2 mm, or about 0.7 mm to about 1.5 mm, or about 0.7 mm to about 1.4 mm, or about 0.7 mm to about 1.3 mm, or about 0.7 mm to about 1.2 mm, or about 0.8 mm to about 1.5 mm, or about 0.75 mm to about 1.4 mm, or about 0.75 mm to about 1.3 mm, or about 0.75 mm to about 1.2 mm, and including all subranges and combinations thereof.

[0045] In another aspect, the present specification provides an evaporative emission control canister system comprising one or more canisters comprising a fuel-side adsorbent volume and at least one vent-side parallel passage adsorbent volume (PPAV), the at least one vent-side PPAV comprising an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface, the parallel passages or channels having a mean channel hydraulic diameter (t) of 1.25 mm or less. c,Dh ), hydraulic diameter cell pitch (CP Dh ), or a combination thereof.

[0046] In some aspects, the present disclosure provides an evaporative emission control canister system comprising one or more canisters having multiple chambers, each chamber defining a volume in fluid communication to allow fluid or vapor to flow unidirectionally from one chamber to the next, a chamber near a fuel vapor inlet (i.e., a fuel port or a fuel tank port) includes a fuel-side adsorbent volume, and one chamber near a vent port includes a vent-side parallel passage adsorbent volume (PPAV), at least one vent-side PPAV includes an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface, the parallel passages or channels having a mean channel hydraulic diameter (t) of 1.25 mm or less. c,Dh ), hydraulic diameter cell pitch (CP Dh ), or a combination thereof.

[0047] In another aspect or embodiment described herein, the present specification provides an evaporative emission control system comprising a fuel tank for storing a fuel, an engine having an air induction system and adapted to consume the fuel, and one or more canisters comprising a fuel-side sorbent volume and at least one vent-side PPAV, the at least one vent-side PPAV comprising an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface, the parallel passages or channels having a mean channel hydraulic diameter (t c,Dh ), hydraulic diameter cell pitch (CP Dh ), or a combination thereof; a fuel vapor inlet conduit connecting the evaporative emission control canister system to a fuel tank; a fuel vapor purge outlet conduit connecting the evaporative emission control canister system to an air induction system of the engine; and a vent conduit for venting the evaporative emission control canister system to atmosphere and for inputting purge air to the evaporative emission control canister system, the vent conduit being formed by a fuel vapor flow path from the fuel vapor inlet conduit to the at least one PPAV to the fuel side adsorbent volume and to the vent conduit, and by an air flow path from the vent conduit to the at least one PPAV to the fuel side adsorbent volume and to the fuel vapor purge outlet.

[0048] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, the mean channel hydraulic diameter (t c,Dh) is, for example, 1.25 mm or less, 1.20 mm or less, 1.10 mm or less, 1.0 mm or less, or about 0.01 mm to about 1.25 mm, about 0.1 mm to about 1.25 mm, about 0.2 mm to about 1.25 mm, about 0.3 mm to about 1.25 mm, about 0.4 mm to about 1.25 mm, or about 0.1 mm to about 1.20 mm, about 0.1 mm to about 1.15 mm, about 0.1 mm to about 1.10 mm, about 0.1 mm to about 1.0 mm, about 0.2 mm to about 1.20 mm, about 0.2 mm to about 1.15 mm, about 0.2 mm to about 1.1 mm, and about 0.4 mm to about 1.0 mm, about 0.4 mm to about 1.25 mm, about 0.4 mm to about 1.20 mm, about 0.4 mm to about 1.15 mm, about 0.4 mm to about 1.1 mm, about 0.4 mm to about 1.0 mm, about 0.4 mm to about 0.95, or about 0.4 mm to about 0.9 mm, and including all subranges and combinations thereof.

[0049] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, the hydraulic diametral cell pitch (CP) of at least one vent-side PPAV described herein may be Dh ) is, for example, 1.50 mm or less, 1.40 mm or less, or 1.30 mm or less, or about 0.5 mm to about 1.5 mm, or about 0.5 mm to about 1.4 mm, or about 0.5 mm to about 1.3 mm, or about 0.5 mm to about 1.2 mm, or about 0.6 mm to about 1.5 mm, or about 0.6 mm to about 1.4 mm, or about 0.6 mm to about 1.3 mm, or about 0.6 mm to about 1.2 mm, if or about 0.7 mm to about 1.5 mm, or about 0.7 mm to about 1.4 mm, or about 0.7 mm to about 1.3 mm, or about 0.7 mm to about 1.2 mm, or about 0.75 mm to about 1.5 mm, or about 0.75 mm to about 1.4 mm, or about 0.75 mm to about 1.3 mm, or about 0.75 mm to about 1.2 mm, and including all subranges and combinations thereof.

[0050] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV comprises: (i) a plurality of channel widths (t c,平均 ), (ii) multiple cell pitch widths (CP) of less than about 1.5 mm tc (iii) a cell density of about 285 to about 1000 cpsi, (iv) a cell wall thickness of less than about 0.5 mm, (v) a BWC of less than about 10 g / dL, (vi) an incremental adsorption capacity of 5% to 50% n-butane at 25° C. of less than about 50 g / L, or (vii) a combination thereof. c,Dh and / or C.P. Dh Any of the options discussed above and all combinations described herein are contemplated.

[0051] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV may include a plurality of channel widths (t c,平均 ) is, for example, less than about 1.25 mm, less than about 1.20 mm, less than about 1.15 mm, less than about 1.1 mm, less than 1.0 mm, or about 0.1 mm to about 1.25 mm, about 0.1 mm to about 1.20 mm, about 0.1 mm to about 1.15 mm, about 0.1 mm to about 1.10 mm, about 0.1 mm to about 1.0 mm, or about 0.2 mm to about 1.20 mm, about 0.2 mm to about 1.15 mm, about 0.2 mm to about 1.1 mm, about 0.2 mm to about 1.0 mm, or about 0.3 mm to about 1.25 mm, about 0.3 mm to about 1.20 mm, about 0.3 mm to about 1.15 mm, about 0.3 mm to about 1.1 mm, about 0.3 mm to about 1.0 mm, or about 0.4 mm to about 1.25 mm, about 0.4 mm to about 1.20 mm, about 0.4 mm to about 1.15 mm, about 0.4 mm to about 1.1 mm, about 0.4 mm to about 1.0 mm, or about 0.4 mm to about 0.9 mm, as well as all subranges and combinations thereof.

[0052] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV may include a plurality of cell pitch widths (CP tc ) is the average of multiple channel widths of channels of approximately the same cross-sectional dimension, not including surrounding channels (i.e., surrounding cells) in the cross-section, plus the average wall thickness of the channels (excluding the outer wall thickness), e.g., less than 1.6 mm, less than 1.55 mm, less than 1.5 mm, less than about 1.45 mm, less than about 1.4 mm, less than about 1.35 mm, less than about 1.3 mm, less than about 1.25 mm, about 0.5 mm to about 1.5 mm, or about 0.5 mm to about 1.4 mm, or about 0.5 mm to about 1.3 mm, or about 0.5 mm to about 1.2 mm, or about 0.6 mm to about 1.5 mm, or about 0.6 mm to about 1.4 mm, or about 0.6 mm to about 1.3 mm, or about 0.6 mm to about 1.2 mm, or about 0.7 mm to about 1.5 mm, or about 0.7 mm to about 1.4 mm, or about 0.7 mm to about 1.3 mm, or about 0.7 mm to about 1.2 mm, or about 0.75 mm to about 1.5 mm, or about 0.75 mm to about 1.4 mm, or about 0.75 mm to about 1.3 mm, about 0.75 mm to about 1.25 mm, or about 0.75 mm to about 1.2 mm, including all subranges and combinations thereof.

[0053] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the cell density (i.e., channels or cells in cross-sectional area per square inch ("cpsi")) of the PPAV can be, for example, about 285 to about 1000 cpsi, about 300 to about 1000 cpsi, about 325 to about 1000 cpsi, about 350 to about 1000 cpsi, about 375 to about 1000 cpsi, about 400 to about 1000 cpsi, about 400 to about 1000 cpsi, about 45 ... psi, about 425 to about 1000 cpsi, about 450 to about 1000 cpsi, about 500 to about 1000 cpsi, about 550 to about 1000 cpsi, about 600 to about 1000 cpsi, or 300 to about 950 cpsi, 300 to about 900 cpsi, about 300 to about 850 cpsi, about 300 to about 800 cpsi, or about 400 to about 900 cpsi, about 400 to about 850 cpsi, about 400 to about 800 cpsi, including all subranges and combinations thereof.

[0054] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the cell wall thickness of the PPAV is, for example, from 0.1 mm to about 0.5 mm, from about 0.1 mm to about 0.45 mm, or from about 0.15 mm to about 0.5 mm, from 0.15 to about 0.4 mm, or from about 0.2 mm to about 0.5 mm, or from about 0.2 mm to about 0.45 mm, including all subranges and combinations thereof. The average channel wall thickness is determined as described herein.

[0055] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the BWC (g / dL) of the PPAV may be, for example, less than about 9.5, less than about 9.0, less than about 8.5, less than about 8.0, less than about 7.5, less than about 7.0, less than about 6.5, less than about 6.0, less than about 5.5, less than about 5.0, less than about 4.5, less than about 4.0, less than about 3.5, less than about 3.0, less than about 2.5, less than about 2.0 g / dL, less than about 1.5 g / dL, less than about 1.0 g / dL, or even less than about 1.0 g / dL. or less than about 0.5 g / dL, or about 0.5 to about 10 g / dL, about 0.5 to about 9 g / dL, about 0.5 to about 8 g / dL, about 0.5 to about 7 g / dL, about 0.5 to about 6 g / dL, about 0.5 to about 5 g / dL, about 0.5 to about 4 g / dL, about 0.5 to about 3 g / dL, about 0.5 to about 2 g / dL, about 0.5 to about 1 g / dL, or about 1 to about 10 g / dL, about 1 to about 9 g / dL, about 1 to about 8 g / dL, about 1 to about 7 g / dL, about 1 to about 6 g / dL, about 1 to about 5 g / dL, about 1 to about 4 g / dL, about 1 to about 3 g / dL, about 1 to about About 2 g / dL, or about 2.0 to about 10, about 2.0 to about 9.5, about 2.0 to about 9.0, about 2.0 to about 8.5, about 2.0 to about 8.0, about 2.0 to about 7.5, about 2.0 to about 7.0, about 2.0 to about 6.5, about 2.0 to about 6.0 g / dL, about 2.0 to about 5.5 g / dL, about 2.0 to about 5.0 g / dL, about 2.0 to about 4.5 g / dL, or about 2.5 to about 10, about 2.5 to about 9.5, about 2.5 to about 9.0, about 2.5 to about 8.5, about 2.5 to about 8.0, about 2.5 to about 7.5, about 2.5 to about 7.0, about 2.5 to about 6. 5, about 2.5 to about 6.0 g / dL, about 2.5 to about 5.5 g / dL, about 2.5 to about 5.0 g / dL, about 2.5 to about 4.5 g / dL, or about 3.0 to about 10, about 3.0 to about 9.5, about 3.0 to about 9.0, about 3.0 to about 8.5, about 3.0 to about 8.0, about 3.0 to about 7.5, about 3.0 to about 7.0, about 3.0 to about 6.5, about 3.0 to about 6.0 g / dL, about 3.0 to about 5.5 g / dL, about 3.0 to about 5.0 g / dL, or about 3.0 to about 4.5 g / dL, including all subranges and combinations thereof.

[0056] Unless otherwise specified, the BWC is determined according to the methods described herein. In any of the aspects or embodiments described herein, the PPAV (i.e., each article or component) described herein has a length of about 25 mm to 250 mm, or about 50 mm to 150 mm.

[0057] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV may have an incremental adsorption capacity (IAC) at 25° C. for 5% to 50% n-butane of, for example, less than about 50 g / L, less than about 45 g / L, less than about 40 g / L, less than about 35 g / L, less than about 30 g / L, less than about 25 g / L, less than about 20 g / L, less than about 15 g / L, less than about 10 g / L, less than about 5 g / L, less than about 4 g / L, less than about 3 g / L, less than about 2 g / L, or less than about 1 g / L, or from about 5 to about 50 g / L, from about 5 to about 45 g / L, less than about ... about 40 g / L, about 5 to about 35 g / L, about 5 to about 30 g / L, about 5 to about 25 g / L, about 5 to about 20 g / L, about 5 to about 15 g / L, about 5 to about 10 g / L, or about 10 to about 50 g / L, about 10 to about 45 g / L, about 10 to about 40 g / L, about 10 to about 35 g / L, about 10 to about 30 g / L, about 10 to about 25 g / L, about 10 to about 20 g / L, or about 15 to about 50 g / L, about 15 to about 45 g / L, about 15 to about 40 g / L, about 15 to about 35 g / L, about 15 to about 30 g / L, about 15 to about 25 g / L, or about 15 to about 20 g / L, including all subranges and combinations thereof.

[0058] In any of the aspects or embodiments of the evaporative emissions control system or evaporative emissions control canister system described herein, the evaporative emissions control canister may be less than or equal to (i.e., less than or equal to) 350, 340, 330, 320, 315, 310, 300, 290, 280, 270, 260, 250, 240, 230, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, or 100 liters, or less than or equal to 150, 140, 130, 120, 110, 100, 90, 80, 75, 70, 65, 60, 55, 50, 45, 40, 55, 60, 55, 70, 75, 80, 85, 90, 95, 100, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 260, 270, 280, 290, 300, 320, 330, 340, 350, 360, 370, 380, 390, 400, 410, 420, 430, 440, 450, 460, 470, 480, 490, 50 With a purging of 0, 35, or 30 or less (i.e., less than or equal to) bed volumes (BV), the 2-day diurnal breathing loss (DBL) is 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1 mg or less (i.e., less than or equal to).

[0059] In any of the aspects or embodiments of the PPAV, evaporative emission control system or evaporative emission control canister system described herein, the PPAV comprises: The PPAV has channels with widths of less than 1.25 mm and a cell pitch of less than 1.5 mm. In some embodiments, the PPAV exhibits low vapor release properties of less than 50 g / L at vapor concentrations of 5 vol% to 50 vol% n-butane as measured by incremental adsorption capacity of 5-50% n-butane at 25° C.

[0060] In any of the aspects or embodiments of the PPAV, evaporative emission control system or evaporative emission control canister system described herein, the PPAV comprises: It has properties exemplified by the experimental results provided herein, including, for example, numerical ranges based on the experimental data.

[0061] In any of the aspects or embodiments of the PPAV, evaporative emission control system or evaporative emission control canister system described herein, the PPAV is in the shape of a prism, e.g., circular (i.e., cylindrical), square, rectangular, triangular, pentagonal, etc., such that parallel passages extend inwardly parallel to each other along the length of the prism and parallel to the exterior surface.

[0062] In any of the aspects or embodiments of the PPAV, evaporative emission control system or evaporative emission control canister system described herein, the PPAV comprises a sorbent material derived from at least one of wood, wood dust, wood flour, cotton linters, peat, coal, coconut, lignite, carbohydrates, petroleum pitch, petroleum coke, coal tar pitch, fruit pits, fruit stones, nut shells, nut pits, sawdust, palm, vegetables, synthetic polymers, natural polymers, lignocellulosic materials, or combinations thereof. In any of the aspects or embodiments described herein, the PPAV comprises a sorbent material derived from wood or wood dust.

[0063] In any of the aspects or embodiments of the PPAV, evaporative emission control system or evaporative emission control canister system described herein, the PPAV includes an adsorbent, for example, activated carbon or carbonized charcoal.

[0064] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV comprises an adsorbent material selected from the group consisting of activated carbon, carbonized charcoal, zeolites, clays, porous polymers, porous alumina, porous silica, molecular sieves, kaolin, titania, ceria, metal organic frameworks, and combinations thereof.

[0065] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV includes one or more binders, such as an organic binder, such as carboxymethyl cellulose (CMC), or an inorganic binder, such as bentonite clay, or a combination of binders. In any of the aspects or embodiments described herein, the PPAV includes one or more cellulosic binders, such as carboxymethyl cellulose (CMC), and one or more inorganic binders, such as clay. In some embodiments, the binder includes at least one of a clay or a silicate material. For example, in some embodiments, the binder is at least one of a zeolite clay, a bentonite clay, a montmorillonite clay, an illite clay, a French green clay, a Pascalite clay, a Redmond clay, a Terramine clay, a living clay, a fuller's earth clay, an Ormalite clay, a Vitallite clay, a Rectorite clay, a Cordierite, a Ball clay, a Kaolin, or a combination thereof.

[0066] Further possible binders include thermosetting binders and hot melt binders. Thermosetting binders are compositions based on thermosetting resins that are liquid or solid at ambient temperature, in particular thermosetting resins of urea-formaldehyde, melamine-urea-formaldehyde or phenol-formaldehyde type, with melamine-urea-formaldehyde type resins being preferred, as well as emulsions of thermosetting (co)polymers in latex foams. Crosslinkers can be incorporated in the mixture. As an example of a crosslinker, ammonium chloride can be mentioned. Hot melt binders are generally solid at ambient temperature and are based on hot melt type resins. As binders, pitch, tar or any other known binders can also be used.

[0067] In any of the embodiments described herein, the binder can include a water-soluble binder (e.g., a polar binder), including, but not limited to, cellulosic binders and related esters including methyl and ethyl cellulose and their derivatives, such as carboxymethyl cellulose (CMC), ethyl cellulose, ethyl methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose, hydroxypropyl methyl cellulose (HPMC), ethyl hydroxyethyl cellulose, crystalline salts of aromatic sulfonates, polyfurfuryl alcohol, polyesters, polyepoxides or polyurethane polymers, and the like.

[0068] In any of the embodiments described herein, the binder can include non-aqueous binders such as clays, phenolic resins, lignin, lignosulfonates, polyacrylates, polyvinyl acetates, polyvinylidene chloride (PVDC), ultra-high molecular weight polyethylene (UHMWPE), and the like, fluoropolymers such as polyvinylidene fluoride (PVDF), polyvinylidene dichloride (PVDC), polyamides (e.g., nylon-6,6′ or nylon-6), high performance plastics (e.g., polyphenylene sulfide), polyketones, polysulfones, and liquid crystal polymers, copolymers with fluoropolymers (e.g., poly(vinylidene fluoride), polytetrafluoroethylene (PTFE), fluorinated ethylene propylene, or perfluoroalkoxyalkanes), copolymers with polyamides (e.g., nylon-6,6′ or nylon-6), copolymers with polyimides, copolymers with high performance plastics (e.g., polyphenylene sulfide), or combinations thereof.

[0069] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV is produced by binder crosslinking of a pulverized precursor activated carbon material, where the pulverized activated carbon material is in the form of a powder. For example, in some embodiments, the shaped PPAV described herein is produced by using a powdered activated carbon material and applying the crosslinking binder technology of U.S. Patent No. 6,472,343.

[0070] Alternatively, or in combination, an inorganic binder may be used. The inorganic binder may be a clay or silicate material. For example, the binder may be at least one of zeolite clay, bentonite clay, montmorillonite clay, illite clay, French green clay, Pascalite clay, Redmond clay, Terramin clay, Living clay, Fuller's earth clay, Ormalite clay, Vitallite clay, Rectorite clay, Cordierite, Ball clay, Kaolin, or a combination thereof.

[0071] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV is formed into a monolithic structure, e.g., a honeycomb structure. In any of the aspects or embodiments described herein, the PPAV monolithic structure is made by a method that includes extruding a blend that includes an adsorbent material and a binder to form a parallel passage shape. In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV (e.g., the PPAV monolithic structure) is made by a method that includes coating the channels of the parallel passage scaffolding with a coating layer that includes an adsorbent material. In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV monolithic structure is made by a method that includes coating the channels of the parallel passage scaffolding with a coating layer that includes a carbonaceous material that is converted in situ into an adsorbent by a separate thermal and / or chemical treatment (e.g., pyrolysis or chemical activation).

[0072] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV monolith structure is made by a method comprising stacking or bending corrugated sheets to form parallel passage shapes. In any of the aspects or embodiments described herein, the parallel passage shapes are made from corrugated sheets containing sorbent. In some embodiments, the parallel passage shapes made from corrugated sheets with sorbent are present in a coating layer. In any of the aspects or embodiments described herein, the PPAV of the evaporative emission control system, or at least one vent-side PPAV described herein, the monolith structure is made by a method comprising co-rolling a solid sorbent sheet or layer with another sheet or another material to create parallel passages. In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV monolith structure is made by a method comprising rolling a solid sorbent sheet or layer with ribs or nubs to shape parallel passages. In any of the aspects or embodiments described herein, the sorbent material is formed into a structure comprising any combination of the foregoing.

[0073] In any aspect or embodiment described herein, the evaporative emission control system or evaporative emission control canister system comprises at least one additional vent-side adsorbent volume having an incremental adsorption capacity at 25° C. of about 2 to about 35 grams per liter (g / L) of n-butane at a vapor concentration of 5 vol% to 50 vol% of n-butane. In any aspect or embodiment described herein, the evaporative emission control system or evaporative emission control canister system comprises at least one additional vent-side adsorbent volume having an incremental adsorption capacity at 25° C. of about 2 to about 30 grams per liter (g / L) of n-butane at a vapor concentration of 5 vol% to 50 vol% of n-butane. In any aspect or embodiment described herein, the evaporative emission control system or evaporative emission control canister system comprises at least one additional vent-side adsorbent volume having an incremental adsorption capacity at 25° C. of about 2 to about 25 grams per liter (g / L) of n-butane at a vapor concentration of 5 vol% to 50 vol% of n-butane. In any aspect or embodiment described herein, the evaporative emission control system or evaporative emission control canister system includes at least one vent-side adsorbent volume having an incremental adsorption capacity at 25° C. of about 2 to about 20 grams per liter (g / L) of n-butane at a vapor concentration of 5 vol% to 50 vol% n-butane.

[0074] In any aspect or embodiment described herein, the evaporative emission control system or evaporative emission control canister system comprises at least one vent-side adsorbent volume having an incremental adsorption capacity at 25° C. of about 2 to about 15 grams per liter (g / L) of n-butane at a vapor concentration of 5 vol% to 50 vol% of n-butane. In any aspect or embodiment described herein, the evaporative emission control system or evaporative emission control canister system comprises at least one vent-side adsorbent volume having an incremental adsorption capacity at 25° C. of about 2 to about 10 grams per liter (g / L) of n-butane at a vapor concentration of 5 vol% to 50 vol% of n-butane.

[0075] In any aspect or embodiment described herein, the evaporative emission control system or evaporative emission control canister system comprises at least one vent-side adsorbent volume having an incremental adsorption capacity at 25° C. of about 2 to about 5 grams per liter (g / L) of n-butane at a vapor concentration of 5 vol% to 50 vol% of n-butane. In any aspect or embodiment described herein, the evaporative emission control system or evaporative emission control canister system comprises at least one vent-side adsorbent volume having an incremental adsorption capacity at 25° C. of about 5 to about 30 grams per liter (g / L) of n-butane at a vapor concentration of 5 vol% to 50 vol% of n-butane.

[0076] In any aspect or embodiment described herein, the evaporative emission control system or evaporative emission control canister system comprises at least one vent-side adsorbent volume having an incremental adsorption capacity at 25° C. of about 10 to about 30 grams per liter (g / L) of n-butane at a vapor concentration of 5 vol% to 50 vol% of n-butane. In any aspect or embodiment described herein, the evaporative emission control system or evaporative emission control canister system comprises at least one vent-side adsorbent volume having an incremental adsorption capacity at 25° C. of about 15 to about 25 grams per liter (g / L) of n-butane at a vapor concentration of 5 vol% to 50 vol% of n-butane.

[0077] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV has a gram-tot BWC of less than 20 g, less than 19 g, less than 18 g, less than 17 g, less than 16 g, less than 15 g, less than 14 g, less than 13 g, less than 12 g, less than 11 g, less than 10 g, less than 9 g, less than 8 g, less than 7 g, less than 6 g, less than 5 g, less than 4 g, less than 3 g, less than 2 g, or less than 1 g. In some embodiments, the PPAV is in an amount of 0.1-20 g, 0.1-20 g, 0.1-19.5 g, 0.1-18 g, 0.1-17.5 g, 0.1-17 g, 0.1-16.5 g, 0.1-16 g, or 0.1-15.5 g, 0.1-15 g, 0.1-14.5 g, 0.1-14 g, 0.1-13.5 g, 0.1-13 g, 0. The PPAV may have a g-tot BWC of 1-12.5g, 0.1-12g, 0.1-11.5g, or 0.1-11g, 0.1-10.5g, 0.1-10g, 0.1-9.5g, 0.1-9g, 0.1-8.5g, 0.1-8g, 0.1-7.5g, 0.1-7g, or 0.1-6.5g, 0.1-6g, 0.1-5.5g, or 0.1-5g, or a g-tot BWC of one or more embodiments. As used herein, "grams-total BWC" refers to the amount of butane purged from the PPAV in grams.

[0078] In any of the aspects or embodiments of the PPAV, evaporative emission control system or evaporative emission control canister system described herein, the PPAV described herein has a cross-sectional hydraulic diameter of between 20 mm and 75 mm, or between about 29 mm and 41 mm.

[0079] In any of the aspects or embodiments of the PPAV, evaporative emission control system or evaporative emission control canister system described herein, the PPAV described herein has a length / hydraulic diameter ratio of about 0.3 to 12.5, or about 1.2 to 5.2.

[0080] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV described herein has about 140 to 6450 channels (or cell cross sections), or about 680 to 1365 channels (or cell cross sections), including partial cells, e.g., cells at the perimeter of a cross section of a cylindrical section. As will be readily apparent to one of ordinary skill in the art, the cells of the PPAV represent a cross section of a channel extending along the interior length of the PPAV. Thus, the number and density of cells is equal to the number and density of channels.

[0081] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV described herein has a diameter of about 60 mm 2 ~2760mm 2 , or about 125 mm 2 ~660mm 2 The total channel area is

[0082] In any of the aspects or embodiments of the PPAV, evaporative emission control system or evaporative emission control canister system described herein, the PPAV described herein has a flow restriction of about 0.01 to 2.7 kPa, or about 0.03 to 0.9 kPa at 40 lpm.

[0083] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the canister system described herein has a total adsorbent particle volume of between 1 liter and 5 liters.

[0084] In any of the aspects or embodiments of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV comprises an adsorbent material selected from the group consisting of activated carbon, carbonized charcoal, zeolites, clays, porous polymers, porous alumina, porous silica, molecular sieves, kaolin, titania, ceria, metal organic frameworks, and combinations thereof.

[0085] The adsorbent material may include any one or more of the above features, which may be combined in any manner in accordance with the present description and are expressly contemplated herein.

[0086] In another aspect, the present disclosure provides an evaporative emissions control system comprising one or more canisters comprising at least one PPAV as described herein.

[0087] FIG. 1 illustrates an exemplary embodiment of an evaporative emission control canister system 100 having serial adsorbent volumes within a single canister. The canister system 100 includes a screen or foam 102, a bulkhead 103, a fuel vapor inlet 104 from a fuel tank, a vent port 105 to atmosphere, a purge outlet 106 to an engine, a fuel side or initial adsorbent volume 201, and a vent side or subsequent adsorbent volume 202. The screen or foam 102 acts as a distributor that not only contains and supports the adsorbent volumes, but also distributes vapor flow into the adsorbent volumes. The two chambers containing the adsorbent volumes 201 and 202 are separated by the bulkhead 103 and connected for continuous vapor flow below the support screen 102 by a passageway 107 called the canister plenum. Thus, in this embodiment, the canister system defines a vapor flow path from the fuel port 104, through the fuel side adsorbent volume 201, the plenum space 107, the vent side adsorbent 202, to the vent port 105. When the engine is off, fuel vapor from the fuel tank enters the canister system 100 through the fuel vapor inlet 104. The fuel vapor diffuses or flows into the fuel side or initial adsorbent volume 201 and into the vent side or subsequent adsorbent volume 202 before being released to the atmosphere through the vent port 105 of the canister system. When the engine is running, ambient air is drawn into the canister system 100 through the vent port 105. Purge air flows through the volume 202 in the canister and finally through the fuel side or initial adsorbent volume 201. This purge flow desorbs the fuel vapor adsorbed in the adsorbent volume 202 and passes through the adsorbent volume 201 before entering the internal combustion engine through the purge outlet 106. As will be appreciated by one of ordinary skill in the art, Figures 2-8 present another exemplary canister system defining an adsorbent volume in fluid communication along a similar fuel vapor / air flow path.

[0088] In any of the embodiments of the evaporative emission control canister system described herein, the canister system may include more than one vent-side or subsequent adsorbent volume. For example, with reference to Figure 2, a fuel-side or initial adsorbent volume 201 may have another or multiple vent-side (or subsequent) adsorbent volumes 202 above the plenum 107 and before the support screen 102, as shown in Figure 2. The other vent-side (or subsequent) adsorbent volumes 203 and 204 may be on opposite sides of the bulkhead.

[0089] Further, in another embodiment, the canister system can include multiple types of vent-side adsorbent volumes that can be independently selected and / or provided in one or more containers. For example, as shown in FIG. 3, a vent-side adsorbent volume 301, e.g., an auxiliary chamber 300 containing a PPAV as described herein, may be connected for vapor flow by a connecting hose or snorkel 108 in series with a main canister 101 containing multiple adsorbent volumes. As shown in FIG. 4, the auxiliary chamber 300 can contain two vent-side adsorbent volumes 301 and 302 in series, e.g., containing at least one PPAV as described herein. The adsorbent volumes 301 and 302 may also be contained in series chambers or auxiliary canisters rather than the single chamber 300 of FIG. 4.

[0090] 5-8 show another exemplary canister system contemplated by the present disclosure. FIGS. 5 and 6 show a system with a main canister 101 with a first (fuel side) sorbent volume 501 and subsequent (vent side) sorbent volumes 202, 203 and 204. The system has a connecting hose or snorkel 108 leading to an auxiliary canister 300 on the vent side, and an additional vent side sorbent volume 502, such as a PPAV as described herein, before the vent port 105. FIG. 7 shows a system with a first (fuel side) sorbent volume 501 and subsequent sorbent volume 202 in the main canister 101, connected via a connecting hose 108 to auxiliary canisters 300 and 503 with subsequent (vent side) sorbent volumes 502, 504 before the vent port 105. In an exemplary embodiment, at least one of 502 or 504 is a PPAV as described herein. 8 shows an example of a single canister 101 design with a first (fuel side) adsorbent volume 501, a plenum space 107 that connects to subsequent (vent side) adsorbent volumes 203 and 204, and a second plenum space 109 that connects to additional subsequent (vent side) adsorbent volumes 502 and 504 before the vent port 105. In an exemplary embodiment, at least one of 502 or 504 is a PPAV as described herein.

[0091] As used herein, the term "upstream" refers to a position / volume in a system flow path that is in contact with a fluid, e.g., fuel vapor, before or prior to other positions / volumes in the system along the flow path in the same relative direction. The term "downstream" refers to a position / volume in a system flow path that is in contact with a fluid, e.g., fuel vapor, after or following an upstream position / volume in the system along the flow path in the same relative direction. That is, when referring to a fuel vapor flow path, an upstream position / volume is closer to a fuel vapor inlet than other positions / volumes.

[0092] The term "fuel-side adsorbent volume" is used in reference to a volume of adsorbent material that is closer to the fuel vapor source and therefore necessarily earlier in the fuel vapor flow path compared to a subsequent adsorbent volume that is located near the vent port (herein "vent-side adsorbent volume"). As one skilled in the art will understand, during a purge cycle, the vent-side or subsequent adsorbent volume is contacted earlier in the purge air flow path. For convenience, the fuel-side adsorbent may be referred to as the "first adsorbent volume" because it is located upstream in the fuel vapor flow path relative to the vent-side or subsequent adsorbent volume, although the first adsorbent volume does not necessarily have to be the first adsorbent volume in the canister.

[0093] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the canister may further comprise additional sorbent volumes as described herein, such as at least one sorbent volume in the chamber closest to the fuel tank (i.e., a fuel-side sorbent volume) and / or at least one sorbent volume closer to the outlet to the atmosphere (i.e., a trailing or vent-side sorbent volume) that contains a PPAV as described herein.

[0094] In another embodiment, the present disclosure provides an evaporative emission control canister system comprising one or more canisters having multiple chambers, each defining a connected or fluidly communicating volume that allows fluid (e.g., air, gas, or fuel vapor) to flow continuously in one direction from one chamber to the next, at least one chamber comprising a PPAV as described herein. In certain embodiments, the canister system comprises at least one additional sorbent volume. In certain embodiments, the sorbent volumes are located within a single canister or within multiple canisters that are connected to allow continuous access by the fuel vapor.

[0095] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the PPAV described herein is incorporated into a vent volume of a 2.1 liter test canister having dimensions as described herein and exhibits a two-day DBL bleed emissions performance (day 2 diurnal breathing loss (DBL) emissions) of about 100 mg or less, about 90 mg or less, about 80 mg or less, about 70 mg or less, about 60 mg or less, about 50 mg or less, about 40 mg or less, about 30 mg or less, about 20 mg or less, or about 10 mg or less.

[0096] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the amount of volatile organic compounds may be from about 10 mg to about 100 mg, from about 10 mg to about 90 mg, from about 10 mg to about 80 mg, from about 10 mg to about 70 mg, from about 10 mg to about 60 mg, from about 10 mg to about 50 mg, from about 10 mg to about 40 mg, from about 10 mg to about 30 mg, from about 10 mg to about 20 mg, from about 15 mg to about 100 mg, from about 15 mg to about 90mg, about 15mg to about 80mg, about 15mg to about 70mg, about 15mg to about 60mg, about 15mg to about 50mg, about 15mg to about 40mg, about 15mg to about 30mg, about 15mg to about 20mg, about 20mg to about 100mg, about 20mg to about 90mg, about 20mg to about 80mg, about 20mg to about 70mg, about 20mg to about 60mg, about 20mg to about 50mg, about 20mg to about 40mg, about 20mg to about 30mg, about 30mg to about 100mg, about 30mg to about 90mg, about 30mg to about 80mg, about 30mg to about 70mg, about 30mg to about 60mg, about 30mg to about 50mg, about 30mg to about 40mg, about 40mg to about 100mg, about 40mg ~90mg, 40mg~80mg, 40mg~70mg, 40mg~60mg, 40mg~50mg, 50mg~100mg, 50mg~90mg, 50mg~80mg, 50mg and about 70 mg, about 50 mg to about 60 mg, about 60 mg to about 100 mg, about 60 mg to about 90 mg, about 60 mg to about 80 mg, about 60 mg to about 70 mg, about 70 mg to about 100 mg, about 70 mg to about 90 mg, about 70 mg to about 80 mg, about 80 mg to about 100 mg, about 80 mg to about 90 mg, or about 90 mg to about 100 mg, including all overlapping and inclusive values ​​and ranges.

[0097] Any of the aspects or embodiments of the evaporative emissions control system or evaporative emissions control canister system described herein, including a PPAV as described herein, provide the above-mentioned two-day DBL bleed emissions performance with a purge of 210 liters (i.e., 100 BV) or less, or 315 liters (i.e., 150 BV) or less, applied after a 40 g / hr butane fill step as measured by the 2012 BETP.

[0098] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the evaporative emission control canister system comprises at least one fuel-side adsorbent volume and at least one subsequent (i.e., vent-side) adsorbent volume, and at least one of the at least one fuel-side adsorbent volume or the at least one subsequent adsorbent volume comprises a PPAV as described herein.

[0099] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the evaporative emission control canister system further comprises a heating unit or means for applying heat by electrical resistance or thermal conduction.

[0100] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the evaporative emission control canister system includes one or more vent-side sorbent volumes having a substantially uniform cell structure at or near the end of the fuel vapor flow path.

[0101] In some embodiments, at least one fuel side or initial sorbent volume and at least one vent side or subsequent sorbent volume(s) are in vapor or gas communication and define air and vapor flow paths therethrough. The air and vapor flow paths enable or facilitate directional air or vapor flow or diffusion between the respective sorbent volumes within the canister system. For example, the air and vapor flow paths facilitate the flow or diffusion of fuel vapor from at least one fuel side or initial sorbent volume to at least one vent side or subsequent sorbent volume(s) containing a PPAV as described herein.

[0102] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the at least one fuel-side or initial adsorbent volume and the at least one vent-side or subsequent adsorbent volume may be located within a single canister, separate canisters, or a combination of both. For example, in some embodiments, the system includes one or more canisters with a fuel-side or initial adsorbent volume and one or more vent-side or subsequent adsorbent volumes that are coupled to the fuel-side initial adsorbent volume and are in vapor or gas communication to form a vapor flow path allowing air and / or vapors to flow or diffuse therethrough, and at least one vent-side adsorbent volume is a vent-side PPAV as described herein. In some aspects, the canister allows air or fuel vapors to contact the adsorbent volumes sequentially.

[0103] In another embodiment, an evaporative emission control canister system comprises a canister with an initial adsorbent volume, and one or more subsequent adsorbent volumes connected to one or more separate canisters with at least one other subsequent adsorbent volume, the subsequent adsorbent volumes being connected to the initial adsorbent volume and in vapor or gas communication to form a vapor flow path allowing air and / or fuel vapors to flow or diffuse therethrough.

[0104] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the evaporative emission control canister system includes one or more canisters having a fuel-side or initial sorbent volume, and one or more vent-side PPAVs having an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface, the parallel passages or channels having a mean channel hydraulic diameter (t c,Dh ), hydraulic diameter cell pitch (CP Dh ), or a combination thereof; and (i) a plurality of channel widths (t c,平均 ), (ii) a cell pitch width (CP) of multiple channels less than about 1.5 mm tc,平均 (iii) a cell density of about 285 to about 1000 cpsi; (iv) a cell wall thickness of less than about 0.5 mm; (v) a BWC of less than about 10 g / dL; (vi) an incremental adsorption capacity of 5% to 50% n-butane at 25° C. of less than about 50 g / L; or (vii) a combination thereof, wherein the fuel side adsorbent volume and the PPAV are in vapor or gas communication and form a vapor flow path allowing air and / or fuel vapor to flow or diffuse therethrough.

[0105] In some embodiments, the evaporative emission control canister system has a two-day diurnal breathing loss (DBL) of 50, 40, 30, 20, or 10 mg or less after a 40 g / hr butane fill step as measured by the 2012 California Bleed Emissions Test Procedure (BETP) with a purge of 315, 300, 290, 280, 270, 260, 250, 240, 230, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, or 100 liters or less, or for applications with 150, 140, 130, 120, 110, 100, 90, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, or 30 bed volumes (BV) or less.

[0106] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the evaporative emission control canister system comprises a canister with a fuel side or first sorbent volume, and a PPAV, where the PPAV is a monolith, e.g., a honeycomb, having an average channel hydraulic diameter of less than 1.25 mm and a hydraulic diameter cell pitch of less than 1.5 mm. In some embodiments, the channels of approximately the same cross-sectional dimension and not including the peripheral channels in the cross-section have channel widths of less than 1.25 mm and cell pitch widths of less than 1.5 mm.

[0107] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the fuel-side or initial adsorbent volume is the first and / or second adsorbent volume, and thus the vent-side or subsequent adsorbent volume comprising the PPAV described herein, whether in the same or a separate canister, or both, is downstream in the fluid flow path toward the vent port.

[0108] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the disclosure provides an evaporative emission control canister system comprising one or more canisters having a plurality of chambers, each chamber defining a volume and in fluid communication to permit unidirectional flow of a fluid or vapor from one chamber to the next, at least one chamber comprising at least one parallel passage adsorbent volume (PPAV), at least one PPAV having an incremental adsorption capacity (IAC) at 25°C of less than 35 g / L at a vapor concentration of n-butane between 5 vol% and 50 vol%, an average channel hydraulic diameter of less than 1.25 mm, and a hydraulic diameter cell pitch (the sum of the average cell channel hydraulic diameter and the average cell wall thickness (excluding the outer wall thickness)) of less than 1.5 mm.

[0109] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the disclosure provides an evaporative emission control canister system comprising one or more canisters with at least one fuel-side adsorbent volume, and at least one vent-side parallel passage adsorbent volume (PPAV), the at least one PPAV having an incremental adsorption capacity (IAC) of less than 35 g / L at 25° C. at a vapor concentration of 5 vol% to 50 vol% n-butane, an average channel hydraulic diameter of less than 1.25 mm, and a hydraulic diameter cell pitch of less than 1.5 mm.

[0110] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the present disclosure provides an evaporative emission control canister system comprising one or more canisters with at least one fuel-side adsorbent volume, and at least one vent-side parallel passage adsorbent volume (PPAV), the at least one PPAV having an incremental adsorption capacity (IAC) of less than 35 g / L at 25° C. at a vapor concentration of n-butane between 5 vol% and 50 vol%, a mean channel hydraulic diameter (t) of less than 1.25 mm, and a vent-side adsorbent volume (VAP) of less than 1.25 mm. c,Dh), and hydraulic diameter cell pitch (CP) of less than 1.5 mm Dh ).

[0111] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the present disclosure provides an evaporative emission control canister system comprising one or more canisters having a plurality of chambers, each chamber defining a volume and in fluid communication to permit unidirectional flow of a fluid or vapor from one chamber to the next, at least one chamber comprising at least one parallel passage adsorbent volume (PPAV), the at least one PPAV having an average channel hydraulic diameter of less than 1.25 mm, an incremental adsorption capacity (IAC) of less than 50 g / L at 25° C. at a vapor concentration of n-butane between 5 vol% and 50 vol%, a plurality of channel widths (t c,平均 ), multiple cell pitch widths less than 1.5 mm (CP tc,平均 ) (which is the average of multiple channel widths of channels of approximately the same cross-sectional dimension, not including surrounding channels or cells within the cross-section, plus the average wall thickness of the channels (excluding the outer wall thickness).

[0112] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the present disclosure provides an evaporative emission control canister system comprising one or more canisters with at least one fuel-side adsorbent volume, and at least one vent-side parallel passage adsorbent volume (PPAV), the at least one vent-side PPAV having an incremental adsorption capacity (IAC) of less than 35 g / L at 25° C. at a vapor concentration of n-butane between 5 vol% and 50 vol%, a plurality of channel widths (t) of less than 1.25 mm, c,平均 ), and multiple cell pitch widths less than 1.5 mm (CP tc,平均 ).

[0113] In any of the aspects or embodiments of the evaporative emission control system or evaporative emission control canister system described herein, the present disclosure provides an evaporative emission control canister system comprising one or more canisters with at least one fuel-side adsorbent volume, and at least one vent-side parallel passage adsorbent volume (PPAV), the at least one vent-side PPAV having an incremental adsorption capacity (IAC) of less than 25 g / L at 25° C. at a vapor concentration of n-butane between 5 vol% and 50 vol%, a plurality of channel widths (t) of less than 1.25 mm. c,平均 ), and multiple cell pitch widths less than 1.5 mm (CP tc,平均 ).

[0114] In another aspect, the present disclosure provides an evaporative emission control canister system comprising a fuel tank for storing a fuel, an engine having an air induction system and configured to consume the fuel, and one or more canisters comprising a plurality of adsorbent volumes including at least one fuel-side adsorbent volume; and at least one vent-side parallel passage adsorbent volume (PPAV) as described herein, wherein the at least one vent-side PPAV has an average channel hydraulic diameter of less than 1.25 mm, an incremental adsorption capacity (IAC) of less than 50 g / L at 25° C. for a vapor concentration of n-butane between 5 vol% and 50 vol%, an average channel hydraulic diameter (t c,Dh ), and hydraulic diameter cell pitch (CP) of less than 1.5 mm Dh a fuel vapor inlet conduit connecting the evaporative emission control canister system to a fuel tank; a fuel vapor purge conduit connecting the evaporative emission control canister system to an air induction system of an engine; and a vent port for venting the evaporative emission control canister system and introducing purge air into the evaporative emission control canister system, wherein the evaporative emission control canister system is defined by a fuel vapor flow path from the fuel vapor inlet conduit through a plurality of adsorber to the vent port, and an air flow path from the vent port through the plurality of adsorber volumes and the fuel vapor purge outlet.

[0115] In a further aspect, the disclosure provides a method for reducing fuel vapor emissions in an evaporative emission control system, the method comprising providing one or more canisters comprising a fuel-side adsorbent volume and at least one parallel passage adsorbent volume (PPAV); and contacting the fuel vapor with the adsorbent volume, the at least one vent-side PPAV having an average channel hydraulic diameter of less than 1.25 mm, and a hydraulic diameter cell pitch of less than 1.5 mm, and optionally an incremental adsorption capacity (IAC) of 50 g / L at 25° C. at a vapor concentration of 5 vol% to 50 vol% n-butane.

[0116] In another aspect, the disclosure provides a method for reducing fuel vapor emissions in an evaporative emission control system, the method including providing one or more canisters comprising a plurality of adsorbent volumes including at least one fuel-side adsorbent volume and at least one vent-side parallel passage adsorbent volume (PPAV), where the at least one vent-side PPAV has an average channel hydraulic diameter of less than 1.25 mm, a plurality of channel widths of less than 1.25 mm, and a plurality of cell pitch widths of less than 1.5 mm, and optionally an incremental adsorption capacity (IAC) at 25° C. of less than 50 g / L at a vapor concentration of n-butane between 5 vol% and 50 vol%.

[0117] In any of the aspects or embodiments described herein, the at least one parallel passage adsorbent volume, or the at least one vent side parallel passage adsorbent volume, has at least one of an incremental adsorption capacity (IAC) of less than 50 g / L at 25° C. with a vapor concentration of n-butane between 5 vol% and 50 vol%, an average channel hydraulic diameter of less than 1.25 mm, and a hydraulic diameter cell pitch of less than 1.5 mm, or a combination thereof. In any of the aspects or embodiments described herein, the at least one parallel passage adsorbent volume, or the at least one vent side parallel passage adsorbent volume, has at least one of an incremental adsorption capacity (IAC) of less than 50 g / L at 25° C. with a vapor concentration of n-butane between 5 vol% and 50 vol%, a plurality of channel widths of less than 1.25 mm, and a plurality of cell pitch widths of less than 1.5 mm, or a combination thereof.

[0118] In any of the aspects or embodiments described herein, the evaporative emission control canister system comprises at least one fuel-side adsorbent volume, at least one vent-side PPAV, and optionally at least one further vent-side adsorbent volume.

[0119] In any of the aspects or embodiments described herein, the sorbent volumes are located within a single canister or within multiple canisters that are linked so as to be continuously accessible by the fuel vapor.

[0120] In any of the aspects or embodiments described herein, at least one vent side PPAV is an activated carbon honeycomb.

[0121] In any of the aspects or embodiments described herein, the at least one separate vent-side adsorbent volume is an activated carbon honeycomb.

[0122] In any of the aspects or embodiments described herein, the activated carbon is derived from a material that includes a member selected from the group consisting of wood, wood dust, wood flour, cotton linters, peat, coal, coconut, lignite, carbohydrates, petroleum pitch, petroleum coke, coal tar pitch, fruit pits, fruit stones, nut shells, nut pits, sawdust, palm, vegetables, synthetic polymers, natural polymers, lignocellulosic materials, or combinations thereof.

[0123] In any of the aspects or embodiments described herein, the morphology of the adsorbent may comprise a member selected from the group consisting of granules, pellets, spheres, honeycombs, monoliths, pelletized cylinders, uniformly shaped particulate media, non-uniformly shaped particulate media, extruded structure media, wound structure media, folded structure media, pleated structure media, corrugated structure media, cast structure media, bonded structure media, nonwovens, woven fabrics, sheets, papers, foams, hollow cylinders, stars, twisted helices, asterisks, formed ribbons, or combinations thereof.

[0124] In any of the aspects or embodiments described herein, the canister system may further comprise a heating unit.

[0125] In any of the aspects or embodiments described herein, the evaporative emission control canister system comprises at least one vent-side parallel passage adsorbent volume (PPAV), wherein the at least one PPAV has an average channel hydraulic diameter less than 1.25 mm and a hydraulic diameter cell pitch less than 1.50 mm, the at least one vent-side PPAV optionally has an effective BWC less than about 10 g / dL, an effective incremental adsorption capacity of n-butane less than about 50 grams per liter (g / L) at 25° C. at a vapor concentration of 5 vol% to 50 vol% n-butane, or a combination thereof.

[0126] Other aspects and embodiments will be apparent to those skilled in the art based on the above description in view of the following examples, which are expressly intended to be part of this specification as expressly set forth herein. EXAMPLES

[0127] Measurement of apparent density, BWC, and powder butane activity

[0128] ASTM D2854 can be used to measure the apparent density of particulate adsorbents, such as granular and pelleted adsorbents of sizes and shapes typically used for evaporative emissions control in fuel systems.

[0129] ASTM D5228 can be used to measure the butane working capacity (BWC) of an adsorption volume containing particulate granular and / or pelleted adsorbents. Butane retention is calculated in g / dL as the difference between the volumetric butane activity (i.e., the apparent density in g / cc multiplied by the butane activity in g / 100g) and the g / dL BWC.

[0130] For powdered activated carbon components for extrusion, powdered butane activity ("pBACT") can be measured by any method known to one of skill in the art that is recognized as equivalent to ascertain its value, i.e., the equilibrium gram weight capacity of an oven-dried powder sample when exposed to an n-butane partial pressure of 1.00 atm for a thermostated sample at 25° C. For example, one suitable alternative for pBACT is based on the ASTM 5228 method described in U.S. Patent Application Publication No. 2019 / 0226426 A1, which is incorporated herein by reference in its entirety.

[0131] A modified version of the ASTM D5228 method can be used to measure the butane working capacity (BWC) of particulate, honeycomb, monolith, and / or sheet adsorbent volumes. A modified version of the ASTM D5228 method can also be used for particulate adsorbents, which include fillers, voids, structural elements, or additives. Additionally, a modified version of ASTM D5228 is used when the particulate adsorbent is not compatible with the standard method ASTM D5228, for example, when it is not easy to fill a representative 16.7 mL adsorbent sample into the test sample tube.

[0132] A modified version of the ASTM D5228 method is as follows: The adsorbent sample (e.g., PPAV honeycomb or monolith) is oven dried at 110±5° C. for a minimum of 3 hours, then placed in a desiccator to cool. The dry mass of the adsorbent sample is recorded. The mass of an empty test assembly (47 mm ID×200 mm length) is measured before assembling the adsorbent sample into the test assembly. The test assembly is then placed in a flow apparatus and charged with n-butane gas at 25° C. and 1 atm pressure at a butane flow rate of 500 ml / min for a minimum of 25 minutes (±0.2 minutes). The test assembly is then removed from the BWC test apparatus. The mass of the test assembly is measured and recorded to the nearest 0.001 gram. This n-butane charging process can be repeated for periods of 5 minutes of continuous flow until a constant mass is achieved. In the examples described herein, the charging and purging times were calculated based on part volume. For example, total butane fill time for a 35 mm diameter x 150 mm long honeycomb was 87-92 minutes. The test assembly may be a container for the honeycomb or monolith parts where the volume can be removed and tested intact. Alternatively, the volume may be part of a canister system or the volume may need to be suitably reconfigured with the contents suitably oriented relative to the gas flow or as they would be encountered in a canister system.

[0133] The test assembly is remounted in the test fixture and purged with 2 liters / min of dry air at 25° C. and 1 atmosphere for a set purge time (±0.2 minutes) selected according to the following formula:

[0134] Purge time (min) = (719 x volume (ml)) / (2000 (ml / min))

[0135] The direction of the air purge flow in the BWC test is the same as the purge flow applied in the canister system. After the purge step, the test assembly is removed from the BWC test apparatus. The mass of the test assembly is measured and recorded to the nearest 0.001 gram within 15 minutes of the end of the test.

[0136] Calculate the butane working capacity (BWC) of the adsorbent sample using the following equation: BWC (g / dL) = amount of butane purged (g) / nominal adsorption volume (dL) Where: Amount of Butane Purged = Mass of Test Assembly After Filling - Mass of Test Assembly After Purging For examples involving a cylindrical PPAV, the following calculation was also used. - Apparent density (g / mL) is calculated by volume (mL) / mass of adsorbent (g). - Adsorption volume (mL) is πD o,c (mm) 2 Calculated as L(mm) / 4000. - Butane activity (g / 100g) is calculated as BACT(g / 100g) = butane loading (g) / (100 x mass of adsorbent (g)). - Butane purge ratio (%) = BPR (%) is calculated as follows: butane purge amount (g) / butane charge amount (g) x 100.

[0137] Measurement of Diurnal Breathing Loss (DBL) Emissions by BETP Testing

[0138] Example evaporative emission control systems were tested by a procedure including the following: For testing using the Type A canister system, the defined 2.1 L canister used to generate the DBL emissions data was of the type illustrated in FIG. 5. Three pellet bed volumes 501, 203, and 204 were placed within the main canister 101, containing 1.40 L, 0.40 L, and 0.30 L of pellets, respectively. The example PPAV honeycomb was present as the adsorbent volume 502 within the auxiliary canister 300, with a seal around the sealing cylinder (not shown in the canister diagram) and thin disks of non-adsorbent open cell foam (102 in FIG. 5) at each end of the honeycomb.

[0139] For tests using Type B canister systems (examples designated herein with a "B" suffix), the adsorbent bed configuration was the same as the Type A system, except that 1) a different, single grade of carbon pellets was used in the main canister, and 2) the two adsorbent volumes 203 and 204 of FIG. 4 were configured as a single 0.70 L volume of pellets as illustrated in FIG. 6. For the example designated "12a+bB", the canister system is Type B, except that two auxiliary canisters are connected in series as shown in FIG. 7. A first auxiliary canister 300 contains a PPAV honeycomb 12a as the adsorbent volume 502, and a second auxiliary canister 503 in series contains a PPAV honeycomb 12b as the adsorbent volume 504, includes a seal (not shown), and includes a non-adsorbent open cell foam disk 102 at each end of the two PPAV honeycombs.

[0140] In the Type A system, there was 1.40 L of NUCHAR® BAX 1500 (Ingevity®, North Charleston, South Carolina, USA) as adsorption volume 501 having a height of about 19.5 cm above support screen 102 located above plenum 107, plus 0.40 L of NUCHAR® BAX 1500 having a height of about 11.1 cm above support screen 102 located above plenum 107, plus 0.3 L of NUCHAR® BAX LBE having a height of about 8.4 cm above support screen 102 between adsorption volumes 203 and 204. Adsorption volume 501 has an average width of 9.0 cm from bulkhead 103 to the right sidewall of the canister, and adsorption volumes 203 and 204 have an average width of about 4.5 cm from bulkhead 103 to its left sidewall. Adsorbent volumes 501, 203, and 204 were of similar depth (into the page of FIG. 5) of 8.0 cm. Each adsorbent bed of pellets was loaded with a dry mass determined by the apparent density that would meet the respective volume target (mass loading = AD x volume target). Table 1 lists the grade and characteristics of the adsorbent volume loading of the main canister. For the Type B canister system, the adsorbent volume in the main canister was loaded only with NUCHAR® BAX 1100LD, as listed in Table 1.

[0141] For tests using a Type C canister, the defined canister used to generate the DBL emissions data was of the type illustrated in Figure 8. This canister system was a commercial canister used in a 2017 model year Honda CR-V vehicle (Evap Family HHNXR01221SA / B). Type C canisters were used in the examples marked 20 a+bC and 21 a+bC, and the Type C system included 1.86 L of NUCHAR® BAX 1100 LD (Ingevity®, North Charleston, South Carolina, USA) as the adsorption volume 501 having a height of about 22.6 cm above the support screen 102 located above the plenum 107, plus 0.26 L of NUCHAR® BAX 1100 LD having a height of about 7.8 cm above the support screen 102 located above the plenum 107, plus 0.23 L of NUCHAR® BAX LBE having a height of about 7.4 cm above the support screen 102 between the adsorption volumes 203 and 204. Adsorbent volume 501 was cylindrical with a diameter of 11.1 cm, and adsorbent volumes 203 and 204 were also cylindrical with an average diameter of about 6.8 cm. Following the gap 109 is a PPAV honeycomb 20a (or 21a) as adsorbent volume 502, and a second PPAV honeycomb 20b (or 21b) in series as adsorbent volume 504, with seals (not shown) and non-adsorbent open cell foam disks 102 at each end of the two PPAV honeycombs.

[0142] Each example canister system was uniformly preconditioned (aged) by repeated cycling of gasoline vapor sorption using certified Tier 3 fuel (8.7-9.0 RVP, 10% ethanol by volume) and 300 bed volumes of dry air purge at 22.7 LPM based on the main canister (e.g., 630 liters for a 2.1 L main canister). The gasoline vapor charge rate was 40 g / hr, with a hydrocarbon composition of 50 vol% and was generated by heating 2 liters of gasoline to approximately 38°C and bubbling air through it at 200 ml / min. Two-liter aliquots of fuel were automatically replaced with fresh gasoline to maintain a near-constant vapor generation rate until breakthrough of 5000 ppm, at which butane was detected by FID or infrared detector. A minimum of 25 aging cycles were used with virgin canisters. Gasoline Working Capacity (GWC) was measured as the average weight gain and loss of charged vapor of the purged vapor over the last 2-3 cycles and is reported as grams per liter of adsorbed volume of the canister system. Further measuring bleed emission performance, the GWC aging cycle was followed by a single butane adsorption / air purge step. Butane was charged at 40g / hr to a breakthrough of 5000ppm at 50% by volume in air at 1 atm, followed by a 1 hour soak and then a 21 minute purge with dry air, with the total purge volume obtained by selecting a constant air purge rate suitable for that period. The canister system was then soaked for approximately 14-18 hours at approximately 25°C with the ports sealed (soak time requirement is 12-36 hours). For the DBL data of Figures 17-22, 25-32, and 42-44, the total purge volume after the single butane adsorbent charge above is 210 L, which corresponds to about 91-95 BV for a complete canister system including all adsorbent volumes present, e.g., the 2.1 L adsorbent volume charge of the defined canister, plus the vent-side activated carbon honeycomb adsorbent 502 located in the subsequent auxiliary canister 300, or the two activated carbon honeycomb adsorbents 502 and 504 located in subsequent series auxiliary canisters 300 and 503.In these configurations, the volume added to the adsorbent pellet volume in the defined main canister was the caliper actual dimensional volume of the activated carbon honeycomb present in auxiliary canister 300 plus the caliper actual dimensional volume of a second activated carbon honeycomb in in-line auxiliary canister 503, if present.

[0143] For the DBL data in Figures 32 and 33, the total purge volumes range from 210 to 310 liters, which corresponds to approximately 94 to 138 BV for a complete canister system including all sorbent volume present. For the DBL data in Figures 34 and 35, the total purge volumes range from 124 to 210 liters, which corresponds to approximately 50 to 85 BV for a complete canister system including all sorbent volume present.

[0144] DBL emissions were then generated by attaching the example tank ports to a fuel tank filled with CARB LEV III fuel (6.9-7.2 RVP, 10% ethanol). The example canister system with the majority of pellets present as BAX 1500 grade carbon in the main canister was connected to a 20 gallon (total volume) tank filled with 6.2 gallons of liquid fuel (13.8 gallons of ullage). The example canister system with BAX 1100 LD in the main canister was connected to a 15 gallon (total volume) tank filled with 4.0 gallons of liquid fuel (11 gallons of ullage). The example Type C canister system was connected to a 14 gallon tank (rated volume) filled with 5.6 gallons of liquid fuel.

[0145] Prior to installation, the filled fuel tank was stabilized at 18.3°C for 18-20 hours while venting (where the soak time requirement while venting is 12-36 hours). The tank and canister system was temperature cycled according to CARB's 2-day temperature profile, increasing the temperature from 18.3°C to 40.6°C over 11 hours each day, then returning to 18.3°C over 13 hours. Emission samples were collected in Kynar bags from the example vent at 6 and 12 hours during the heating phase (to allow the fuel in the tank to reach peak temperature). The Kynar bag was filled with nitrogen to a known total volume based on pressure, and vented into the FID to determine the hydrocarbon concentration. The FID was calibrated with a precisely known butane standard with a concentration of approximately 5000 ppm. Emissions were calculated (as butane) based on the Kynar bag volume, emission concentration, and ideal gas assumptions. 6 and 12 hours of emissions were added each day. In accordance with CARB procedures, the day with the highest total emissions was reported as the "2-day emissions." In all cases, except for Example 24, the highest emissions were obtained on the second day. For Example 24, the first day emissions were 278 mg, while the second day emissions were 178 mg. This procedure is generally described in SAE Technical Paper 2001-01-0733, entitled "Impact and Control of Canister Bleed Emissions," by RS Williams and CRC Clontz, as well as in CARB's LEV III BETP procedure (Section D.12 of California Evaporative Emissions Standards and Test Procedures for 2001 and Subsequent Model Motor Vehicles, March 22, 2012).

[0146] [Table 1]

[0147] Measuring flow limitation

[0148] For honeycomb PPAV monoliths, flow restriction (kPa) was measured from 10 to 100 slpm in 10 slpm increments using a PPAV holder typically used for canister system testing (e.g., holder 300 shown in Figures 3-5). A correction for flow restriction was applied for the pressure drop of an empty holder at the same flow rate. A quadratic equation was used to fit the flow restriction data as a function of flow rate. Data are reported here as calculated flow restriction at a flow rate equivalent to 40 slpm and a superficial velocity of 46 cm / sec, taking into account the cross-sectional area of ​​the monolith, measured in diameter with a caliper. For the canister system with a main canister and an auxiliary canister containing a PPAV monolith on the vent side, flow restriction was measured under pressurized fill flow from fuel tank port 104 to vent port 105 with engine purge port 106 closed ("system fill dP") and under pressurized purge flow from vent port 105 to engine port 106 with fuel tank port 104 closed (system purge dP) in Figures 3-5. A quadratic equation was used to fit the flow restriction data as a function of flow rate and system fill, and purge dP is reported here at 40 slpm calculated.

[0149] Measurement of dynamic butane adsorption capacity

[0150] PPAV honeycomb monolith component samples were placed in a vertically oriented cylindrical sample holder and tested for dynamic adsorption capacity (DAC) following a fill-purge-refill procedure in a chamber at 25° C. (see U.S. Patent Application Publication No. 2020 / 0018265 A1, incorporated herein by reference in its entirety).

[0151] For the DAC test, the sample and its holder were first weighed and then filled with 25C, 1:1 n-butane:N2 test gas flow (50 vol% n-butane) at 134 mL / min (9.5 g / hr butane flow) until saturated. The flow direction was downward from the top to the bottom of the sample holder. The gas composition of the exit flow from the sample holder was monitored by an Emerson X-STREAM IR spectrometer. After the saturation step, the sample and its holder were reweighed and then briefly purged with N2 at 100 mL / min for 10 min in the same flow direction as saturation. After the brief purge, the sample and its holder were reweighed and desorbed with 10 L / min N2 flow in the opposite flow direction to the initial saturation flow direction relative to the sample (i.e., 10 L / min purge gas flow was downward, but with the sample inverted 180°) for 15 min. In the next step, after a final standard 5 min pause for mechanical adjustment, the gas composition was switched to a mixture of 0.5 vol% butane in N2 at 134 ml / min (0.1 g / h butane flow rate). This loading step was also performed as a downward flow with the same flow direction as for the initial saturation of the sample (i.e., the 0.5 vol% butane flow was downward, but the sample was flipped 180° with respect to its original direction). The breakthrough curve of the adsorbate in the effluent stream was recorded using the IR spectrometer as described above.

[0152] The key measured response of the PPAV portion in the DAC test is the effluent concentration as the sample becomes progressively saturated throughout the length of the adsorbent volume, including any background leakage of adsorbent emissions, called bleed-through, and the breakthrough of the elution curve of the adsorbent concentration gradient through the volume, known as the mass transfer zone (MTZ). Thus, there are three periods in this adsorption progression: 1) an initial period of bleed-through during which the adsorbate in the effluent is at a relatively stable zero or low concentration, when all or nearly all of the influent adsorbate is removed by the adsorbent bed; 2) a period of accelerating and then decelerating adsorbate concentration rise in the effluent stream, if there is MTZ breakthrough; and 3) a final period of complete equilibrium saturation of the adsorbent bed following MTZ breakthrough, when the adsorbent bed reaches thermal and concentration equilibrium with the influent stream throughout its entire length. As is typical in the art, the MTZ elution curve is quantified by the point at 5% of the influent adsorbate concentration detected in the effluent, and the point at 95% of the influent adsorbate concentration detected in the effluent. A high efficiency adsorbent bed has a sharp MTZ such that the mass of adsorbate in the effluent prior to saturation is minimized, i.e., the potential capacity of the adsorbent bed for a greater proportion of the adsorbate is utilized compared to the loss in the effluent at some point in the MTZ concentration breakthrough (BT). If there is a residual heel of adsorbate in the adsorbent bed from previous contact with the adsorbate, such as from successive adsorption and purge steps, prior to MTZ breakthrough, a large amount of bleed-through can occur, allowing the incoming adsorbate flow unimpeded through the bed.

[0153] For an unused PPAV fraction (i.e., no adsorbate at t=0 time), the effluent curve will typically have the appearance of Figure 14. The key point in the effluent curve is the point at which the influent adsorbate concentration is 5% in the effluent after the first bleed-through concentration, t v5% and the time when the effluent adsorbate concentration reaches 95% of the difference between the initial bleed-through concentration and the influent adsorbate concentration, "the time of 95% BT after the initial bleed-through", time t v95% (For an unused adsorbent bed, bleed-through is nearly zero, so t v5% is essentially the 5% time that the influent is measured in the effluent, and tv95% is the time that the influent concentration is present in the effluent 95% of the time). v5% From the mass balance of the inflow and outflow of the adsorbent stream over time, the cumulative mass adsorbed by the bed is m ads,V5% (The shaded area in Fig. 14, t=0 and t v5% and the cumulative mass of adsorbed matter in the effluent is m efl,V5% The initial adsorption efficiency DAE V5% is the amount adsorbed up to that time, m ads,V5% is the ratio of the adsorbate delivered to the adsorbent bed over that period to the total inlet mass (e.g., m ads,V5% m efl,V5% +m ads,V5% (ratio to time t v95% The cumulative mass adsorbed on the bed by the time m ads,V95% The mass of adsorbate in the effluent during this period of MTZ breakthrough can be separated into two contributions: 1) the effluent mass due to successive bleed-throughs based on the initial bleed-through concentration at t = 0, m efl,VB5-95% (approximately equal to zero for unused adsorbent beds), 2) remaining effluent mass, m efl,VM5-95% , which includes the mass resulting from passing through the MTZ of 5 to 95% of the breakthrough. v95% The total mass of the outflow during the period is m efl,V95% and m eflV5% +m efl,VB5-95% +m efl,VM5-95% It is equal to the sum of t=0~t v95% Adsorption efficiency during the period, DAE V95% is the cumulative adsorption amount up to that point, m ads,V95% of the total inflow mass of adsorbate delivered to the adsorbent bed over that period, m del,V95% (e.g., DAE V95% m ads,V95% m del,V95% is the ratio to m ads,V95% m ads,V95% +m efl,V95% (equal to the ratio of

[0154] For the PPAV portion that underwent the adsorption and purging pre-step in the dynamic adsorption test, the effluent concentration response is similar to that in Figure 15, and a mass balance similar to that applied to the virgin PPAV portion can be applied to the recycled PPAV portion, and the dynamic adsorption efficiency can be derived similarly. C5% From the mass balance of the inflow and outflow of the adsorbent stream over time, the cumulative mass adsorbed by the bed is m ads,C5% (The shaded area in Fig. 15, t=0 and t C5% and the cumulative mass of adsorbed matter in the effluent is m efl,C5% The initial adsorption efficiency DAE C5% is the amount adsorbed up to that time, m ads,C5% is the ratio of the adsorbate delivered to the adsorbent bed over that time to the total inlet mass (e.g., m ads,C5% m efl,C5% +m ads,C5% (ratio to time t C95% By this time, most of the MTZ has flowed into the bed effluent and the cumulative mass adsorbed on the bed is m ads,C95% The mass of adsorbate in the effluent during this period of MTZ breakthrough can be separated into two contributions: 1) the effluent mass due to successive bleed-throughs based on the initial bleed-through concentration at t = 0, m efl,CB5-95% (which can be significantly more measurable for recycled adsorbent beds), 2) remaining effluent mass, m efl,CM5-95% , which includes the mass resulting from passing through the 5 to 95% breakthrough MTZ, defined by the first bleed-through as the breakthrough concentration baseline. t=0 to t C95% The total mass of the outflow during the period is m efl,C95% and m efl,C5% +m efl,CB5-95% +m efl,CM5-95% It is equal to the sum of t=0~t C95% Adsorption efficiency, DAE C95% is the cumulative adsorption amount up to that point, m ads,C95% of the total inflow mass of adsorbate delivered to the adsorbent bed over that period, m del,C95% (e.g., DAE C95% m ads,C95% mdel,C95% is the ratio to m ads,C95% m ads,C95% +m efl,C95% Given a significant measurable concentration of the PPAV portion of the circulation, the bleed-through is expressed as an absolute mass value (m efl,C5% ) can be compared between the examples, and the mass value (m del,C95% ), and the mass value relative to the total adsorbed mass (m del,C95% ) can be used for comparison.

[0155] In addition to analysis of the effluent data at 5% and 95% breakthrough of the recycled PPAV for bleed-through and efficiency, analysis of the effluent data was performed at 25% of the inlet 0.5 vol% butane, i.e., an intermediate breakthrough of 0.125 vol% butane in the effluent (see U.S. Patent Application Publication No. 2020 / 0018265 A1). Figure 16 illustrates the derivation of the effluent mass value from the intermediate breakthrough of 0.125 vol% adsorbate in the effluent.

[0156] Pore ​​volume and surface area determination

[0157] The volume (PV) of pores with sizes between 1.8 nm and less than 100 nm is measured by nitrogen adsorption porosimetry by nitrogen gas adsorption method ISO 15901-2:2006 using a Micromeritics ASAP 2420 (Norcross, GA). The sample pretreatment procedure for nitrogen adsorption testing was to degas at 250 °C for at least 2 h and then isolate the sample to a stable vacuum of less than 2 μm Hg, typically. Measurements of pore volume for pores with sizes between 1.8 nm and less than 100 nm were from the desorption branch of the isotherm at 77 K for 0.1 g of sample. Nitrogen adsorption isotherm data was analyzed with the Kelvin and Halsey equation to determine the distribution of pore volume with pore size for cylindrical pores according to the Barrett, Joyner, and Halenda model ("BJH"). The non-ideality factor was 0.0000620. The density conversion factor was 0.0015468. The diameter of the thermally evaporated hard sphere was 3.860 Å. The molecular cross-sectional area was 0.162 nm2. The thickness of the condensed layer (Å) related to the pore diameter (D, Å) used in the calculation was 0.4977[ln(D)]2-0.6981ln(D)+2.5074. The target relative pressures for the isotherms were as follows: 0.04, 0.05, 0.085, 0.125, 0.15, 0.18, 0.2, 0.355, 0.5, 0.63, 0.77, 0.9, 0.95, 0.995, 0.95, 0.9, 0.8, 0.7, 0.6, 0.5, 0.45, 0.4, 0.35, 0.3, 0.25, 0.2, 0.15, 0.12, 0.1, 0.07, 0.05, 0.03, 0.01. The actual points were recorded within the absolute or relative pressure tolerance range of 5 mmHg or 5%, whichever is tighter, respectively. The time between successive pressure measurements during equilibration was 10 seconds. The pore volumes were calculated according to the defined pore range, e.g., pore volumes with sizes less than 1.8 nm (<18 Å) are PV <1.8nm It is reported that:

[0158] Measurement of incremental adsorption capacity

[0159] Micromeritics Methods As is known in the art, adsorption capacity may be equivalently measured by a number of means, including volumetric, gravimetric, and kinetic (flow) methods.

[0160] The "Micromeritics method" is a volumetric method based on a gas-phase mass balance of an adsorbent sample-containing system of known volume and temperature when exposed to changes in adsorption gas-phase pressure. In the examples herein, a Micromeritics model ASAP 2020A expansion unit (Micromeritics Instrument Corporation, Norcross, GA USA) was used. With this method, as an initial condition, the adsorbate gas is placed in one vessel of known temperature, pressure, and volume, and the adsorbate gas is placed in a second adsorbent-containing vessel of known volume and temperature, and known, different pressure. The two vessels are then brought into fluid contact by opening the connecting valve. After equilibration to the final condition (i.e., a time sufficient for thermal equilibration and uptake of the equilibrated adsorbate by the adsorbent sample, as evidenced by a stable connecting system pressure), the difference in the gas-phase adsorbate mass balance between the initial condition and the final condition is the mass change of the adsorbate adsorbed by the adsorbent sample. Note that in all examples reported herein, the adsorbate is n-butane.

[0161] The first step in determining the IAC is sample preparation. A representative adsorbent sample is oven dried at 110°C for >3 hours. If the apparent density value measurement includes the masses of inert binders, fillers, and structural elements equally in the numerator of its mass, then the adsorbent sample includes the representative amounts of inert binders, fillers, and structural elements in the nominal volume of the adsorbent element. Conversely, if the apparent density value excludes the masses of inert binders, fillers, and structural elements equally in the numerator, then the adsorbent sample excludes these inert binders, fillers, and structural elements. The universal concept is to accurately define the adsorption properties for butane on a volumetric basis in volume.

[0162] The quartz sample tube with rubber stopper is weighed and the weight is recorded (WO). Approximately 0.1 g of the adsorbent sample is loaded into the tared sample tube and the rubber stopper is replaced. The rubber stopper is removed and the filled sample tube is placed under the degassing port and the temperature is increased to 250°C at a rate of 10°C / min. The sample is degassed at 250°C for approximately 2 hours. The sample is cooled and the tube is backfilled with nitrogen. The rubber stopper is replaced and the degassed tube is weighed (W). The dry sample weight is calculated as W-WO. The second step of the procedure is the sample analysis. The water bath is set to 25±0.1°C. The instrument sample pressure is vented to less than 10 μmHg (usually less than 1 μmHg). The instrument plug and sample rubber stopper are removed and the degassed tube is placed in the sample analysis port. The test is started. The instrument collects equilibrium butane isotherm data points near the following absolute pressures: 10, 20, 30, 40, 45, 150, 300, 350, 400, 450, 600, 800, 600, 500, 450, 400, 350, 300, 150, 50, 45, 40, 35, 30, and 25 (mmHg). The 0.5 vol% mass adsorption isotherm data points at 1 atm (3.8 mmHg) reported here are based on a power law regression (mass adsorption = pressure) derived from the fit of the 10, 20, 30, and 40 mmHg isotherm data points. b ) was calculated.

[0163] The IAC is defined as the incremental adsorption capacity of n-butane from 5 to 50% at 25°C. The 5 vol% n-butane concentration (volume concentration) at one atmosphere is given by an equilibrium pressure of 38 mmHg inside the sample tube. The 50 vol% n-butane concentration at one atmosphere is given by an equilibrium pressure of 380 mmHg inside the sample tube. Because equilibration at exactly 38 and 380 mmHg may not be easily obtained, the mass of adsorbed n-butane per mass of adsorbent sample at 5 vol% and 50 vol% n-butane concentrations is interpolated from the graph using data points collected near the target pressures of 38 and 380 mmHg. In the examples provided herein, this was typically done using a linear regression of pressures of about 300 to about 450 mmHg on the desorption branch of the isotherm with pressures of about 30 to 45 mmHg. Using the ideal gas law for n-butane and the apparent density of the adsorbent, the IAC can be calculated as the capacity at 50 vol% n-butane (g / g) minus the capacity at 5 vol% n-butane multiplied by the apparent density in g / L.

[0164] The McBain method is a gravimetric method. The adsorbent sample is oven dried at 110°C for >3 hours and then loaded onto a sample pan attached to a spring in a sample tube. The sample tube is then attached to the described apparatus. If the apparent density value measurement includes the masses of inert binders, fillers, and structural elements equally in the numerator of its mass, the adsorbent sample includes representative amounts of inert binders, fillers, and structural elements in the volume of the adsorbent element. Conversely, if the apparent density value excludes the masses of inert binders, fillers, and structural elements equally in the numerator, the adsorbent sample excludes these inert binders, fillers, and structural elements. The universal concept is to precisely define the adsorption properties for butane on a volumetric basis in volume.

[0165] A vacuum of less than 1 torr is applied to the sample tube and the adsorbent sample is heated at 105 °C for 1 h. The mass of the adsorbent sample is then measured by the amount of spring extension using a cathetometer. The sample tube is then immersed in a water bath temperature-controlled at 25 °C. When the pressure in the sample tube reaches 10 -4Air was evacuated from the sample tube until the equilibrium pressure reached about 38 torr. n-butane was introduced into the sample tube until equilibrium was reached at the selected pressure. Tests were performed for two data sets of four selected equilibrium pressures, acquired at about 38 torr and about 380 torr, respectively. The concentration of n-butane was based on the equilibrium pressure in the sample tube. After each test at the selected equilibrium pressure, the mass of the adsorbent sample was measured based on the extension of the spring using a cathetometer. The increased mass of the adsorbent sample was the amount of n-butane adsorbed in the adsorbent sample. For each test, the mass (grams) of n-butane adsorbed per mass (grams) of the adsorbent sample was measured at various n-butane equilibrium pressures and plotted on a graph as a function of the concentration (volume %) of n-butane. A concentration (volume concentration) of 5 vol% n-butane at one atmosphere is given by an equilibrium pressure of 38 torr inside the sample tube. A concentration of 50 vol% n-butane at one atmosphere is given by an equilibrium pressure of 380 torr inside the sample tube. Because equilibration at exactly 38 and 380 torr may not be easily obtained, the mass of n-butane adsorbed per mass of adsorbent sample at 5 vol% n-butane concentration and 50 vol% n-butane concentration is interpolated from the graph using data points collected near the target pressures of 38 and 380 torr. The IAC is then calculated as described herein.

[0166] Determination of effective volumetric properties

[0167] The above method is applicable to define the nominal BWC, butane activity, IAC, and density properties of the adsorbent. In contrast, the effective volume of the adsorbent takes into account the air gaps, voids, and other volumes interposed between the nominal volumes of the adsorbent along the vapor flow path where there is no adsorbent. For example, those volumes without adsorbent include, but are not limited to, the volume between adsorbent volumes 301 and 302 in FIG. 4, the volume between adsorbent volumes 204 and 301 in FIG. 4 including the port 108 and the connecting conduit between the canisters 101 and 300, and the volume between adsorbent volumes 202 and 203 in FIG. 4 including the plenum volume 107. Thus, the effective volume properties of the adsorbent refer to the volume-averaged properties of the adsorbent volume, taking into account the air gaps, voids, and other volumes between the nominal volumes of the adsorbent along the vapor flow path where there is no adsorbent.

[0168] The effective volume (V 有効 ) is the nominal volume of the adsorber present along the vapor path length (V 呼び,i ) and the adsorbent-free volume along the vapor flow path (V ギャップ,j ) is the sum of V 有効 =ΣV 呼び,i +ΣV ギャップ,j

[0169] Volumetric adsorption properties of effective volume (B 有効 ), e.g., incremental adsorption capacity (g / L), apparent density (g / mL), and BWC (g / dL) are each properties of the individual nominal volumes that are considered as part of the effective volume (B 呼び,i ) to each individual nominal volume (V 呼び,i ) and then multiply them by the total effective volume (V 有効 ) is the result. B 有効 =Σ(B 呼び,i xV 呼び,i ) / V 有効

[0170] Thus, the term "effective incremental adsorption capacity" is the sum of each nominal incremental adsorption capacity multiplied by each individual nominal volume, then divided by the total effective volume.

[0171] The term "effective butane working capacity (BWC)" is the sum of each BWC value multiplied by each individual nominal volume, then divided by the total effective volume.

[0172] The term "effective apparent density" is the sum of each apparent density multiplied by each individual nominal volume and then divided by the total effective volume.

[0173] The term "g-Total BWC of effective volume" is the sum of the g-Total BWC gram values ​​of the nominal volumes within the effective volume.

[0174] In any of the aspects or embodiments, the present specification provides a PPAV as described herein having an effective BWC (e.g., an effective BWC of less than about 10 g / dL, or a value described for BWC herein), an effective IAC (e.g., an effective IAC of less than about 50 g / L, or a value described for IAC herein), an effective apparent density, a g-total BWC of effective volume, or a combination thereof, in an evaporative emission control canister system.

[0175] Determination of honeycomb dimensions and cell structure

[0176] 9 is an idealized overall view of a honeycomb cross-section 600 for purposes of illustrating the main structural features, including the outer edge or exterior surface 601, the parallel channels (or cell cross-sections) 602, the cell walls 603, and the peripheral edge walls or "outer walls" 604. The channels are spaced apart by a width t c , cross-sectional area A c , and the perimeter P c The cells have a wall thickness t w The outer wall has a thickness of t s has.

[0177] To determine the cross-sectional dimensions, an example honeycomb part was cut into 1 mm thick slices with a diamond blade saw. The slice was then placed on a piece of white printer paper with a ruler for scale reference and aligned with the horizontal and vertical axes in the camera viewfinder, with the square grid of cells at the same level and in the rotated orientation shown in Figure 9. The piece of paper and sample slice were placed on a 5000°K color-corrected lamp light box and a DSLR camera (Cannon EOS Rebel T3) was mounted on top to take pictures. The camera was approximately 7.5 inches above the light box and was fitted with a 50 mm fixed lens (1:1.8) and a 13 mm extension lens barrel. Using backlighting of the slice, multiple pictures of the cross-sectional slice were taken at different camera positions to obtain a clear image. Images were analyzed by ImageJ, a public domain, Java-based image processing free software program developed at the National Institutes of Health and the Laboratory for Optical and Computational Instrumentation. The pixels of the digital images were calibrated and lines drawn across the surface of the images provided various measurements of diameter, width, and thickness. Channel area was analyzed with the "Analyze particle" command. Typically, image analysis was measured on slices from one to five sample parts from the same preparation lot as the part tested for DBL emissions, and the average of these dimensional analysis values ​​are reported in Tables 2-6.

[0178] 10 and 11 show the outer diameter D of the honeycomb 600. o and inner diameter D i The four rotational orientations of 0°, 45°, 90°, and 135° are shown, which are applied to measure the outer diameter, DBL emission (D o,キャリパー ) were measured with the caliper of the same example part tested. Four rotation measurements, D o,キャリパー The average values ​​are shown in Tables 2 to 6. The part length L was also measured with a caliper.

[0179] For the high aspect ratio, slit shaped cell example, the PPAV sections were characterized by measuring the channel width and wall thickness separately according to the orientation of the wide and narrow channel widths of their components. The x-axis refers to measurements made in the wide width direction, which is oriented as the width of the wide channel, in the direction of lines 901 and 903 in FIG. 12 for the cross-hair analysis, and in the direction of lines 911 and 911 in FIG. 13 for the nxn analysis (see also FIG. 46), with all channels extending in this same horizontal direction. The y-axis refers to measurements made in the narrow width direction, which is oriented as the height of the narrow channel, in the direction of lines 902 and 904 in FIG. 12 for the cross-hair analysis, and in the direction of lines 912 and 914 in FIG. 13 for the analysis of the nxn crop.

[0180] Tables 2 to 6: Inner diameter to outer diameter, outer wall thickness t s,D is the outer diameter D of the image analysis o and inner diameter D i and the four rotation measurements at both diameters, i.e., D o,0° , D o,45° , D o,90° , D o,135° The average value of and D i,0° , D i,45° , D i,90° , D i,135° Based on the average value of.

[0181] Use image analysis to determine the total channel cross-sectional area (A c ) and perimeter (P c ) was obtained using the “Analyze particle” command. The mean channel hydraulic diameter (t c,Dh ) is 4ΣA c / ΣP c was calculated.

[0182] 12 and 13 show two structures used by image analysis to measure cell wall thickness, from which the average wall thickness value t w,平均was calculated and then applied to the average cell pitch calculation. In one construction for measuring wall thickness (FIG. 12), four crosshairs were drawn through the approximate center of the slice cross section, two through the middle of the cell (lines 901 and 902) and two facing the base of the cell (lines 903 and 904), with the ends of all four lines extending only to the inner walls of the surrounding cells. The mid-cell wall thickness t w,m , and the base cell wall thickness t w,b is determined as the average of the wall thicknesses intersected by the intermediate cell lines 901 and 902 and the base cell lines 903 and 904, respectively. In the exemplary embodiment of FIG. 12, each of the lines 901-904 intersects seven channels and eight cell walls. In a second structure for measuring wall thickness (FIG. 13), an "nxn" crop of square cells is selected from the cross-sectional plane, where the crop does not include any peripheral cells (i.e., those located on the outer walls). Four intermediate cell lines are drawn through the centers of the peripheral cells of the crop, shown as lines 910-913 in FIG. 13, with the ends of all four lines extending only to the corner channels of the peripheral cells. The wall thickness t of the nxn crop w,nxnは , was the average of all wall thicknesses intersected by lines 910-913. In the exemplary embodiment of FIG. 13, each of lines 910-913 intersects five channels and four cell walls. For a given cross-sectional slice that is the subject of image analysis, the average wall thickness t w,平均 t w,m , t w,b , and t w,nxn was calculated as the average.

[0183] Channel width t c,平均 is taken from multiple channels of a honeycomb cross section with approximately the same cross-sectional dimensions, without partial cells at the periphery. The channel width t c,平均 is the channel width t c,m , t c,b , and t c,nxn For example, the channel width t c,m was the average channel width of the cells intersected by the middle cell lines 901 and 902 in FIG. 12.c,b was the average channel width of the cells crossed by the base cell lines 903 and 904 in FIG. c,nxn was determined using particle analysis by identifying all cells in the crop region, which yields the area of ​​each cell (void area). The average cell area was calculated and used to determine the channel width using the square root of the area (i.e., t c,nxn =(A c,平均 )^1 / 2).

[0184] CP, which is one value of cell pitch Dh was calculated from the average channel hydraulic diameter of the entire honeycomb cross-sectional area including all cells: t c,Dh and w,平均 The sum of the second cell pitch CP tc is based on the channel width of multiple channels having approximately the same cross-sectional dimensions, not including partial cells on the periphery. The cell pitch of multiple channels, CP tc t c,平均 and w,平均 is the sum of.

[0185] The ratio of the exterior surface to solid volume Sv of the honeycomb PPAV embodiment is the ratio of the total channel wall surface area (total channel perimeter x caliper length) plus the sum of the solid wall areas on both sides divided by the caliper determined volume corrected for the porosity ε determined by image analysis, or [(ΣP c )L+επD o,c 2 / 4] / [(1-ε)V].

[0186] Exemplary embodiments

[0187] With reference to the accompanying tables and figures, the parallel path adsorption volume (PPAV) examples were activated carbon honeycombs prepared using a ceramic binder system and activated carbon powder as well as the component types and process steps outlined in U.S. Pat. No. 5,914,294 (incorporated herein by reference in its entirety), i.e., a mixture of ball clay, flux, organic extrusion aid, activated carbon, and calcined kaolin, followed by extrusion, drying, and high-temperature calcination. Comparative Examples 1 and 12a were commercially available NUCHAR® HCA honeycomb parts. Comparative Example 12b was a commercially available NUCHAR® HCA-LBE honeycomb part (Ingevity®, North Charleston, South Carolina, USA). Examples 2-9 were made using NUCHAR® RGC-PC acid-activated wood-based carbon powder (Ingevity®, North Charleston, South Carolina, USA) and had the following properties: mean particle size of 21.4 microns, d of 3.8 microns, d of 1.0 ... 10% , d of 15.5 microns 50% , d of 34.1 microns 90% , powdered butane activity (pBACT) of 44.8g / 100g, PV of 0.185cc / g <1.8nm , PV of 0.678cc / g 1.8-5nm , PV of 0.285cc / g 5-50nm , and 1607m 2 Examples 10 and 11 were made using Sabre Series® heat-activated coconut-based carbon powder (Carbon Resources, Oceanside, California, USA) with the following properties: average particle size of 18.0 microns, d of 3.6 microns, 10% , d of 16.3 microns 50% , d of 39.4 microns 90% , powdered butane activity (pBACT) of 29.4 g / 100 g, PV of 0.470 cc / g <1.8nm , PV of 0.114cc / g 1.8-5nm , and a PV of 0.025 cc / g 5-50nm , and 1226m 2 / g BET area.

[0188] In preparing the example PPAV honeycombs, the channel width, wall thickness, and cell pitch were varied by the size and spacing of the slots and pins machined in the extrusion die (see, e.g., U.S. Patent No. 6,080,348, incorporated herein by reference in its entirety). The majority of the examples were extruded with dies that produced square cross-sectional channel shapes, with two notable comparative examples having rectangular or "slit" cross-sectional channel shapes. By adjusting the blend ratios of the mixed components, particularly the activated carbon blend ratio, to account for the various porosities in the finished product resulting from the die selection, a similar range of BWC and IAC could be achieved in the finished PPAV honeycombs for the inventive and comparative examples. In some cases, an additional glass microsphere powder component was added as a diluent to further adjust the volume of the adsorption capacity.

[0189] Table 2 provides structural properties of comparative and inventive examples of exemplary parallel passage adsorbent volumes in the form of activated carbon honeycombs approximately 35 mm in diameter and 150 mm in length within a BWC range of 4.1-4.7 g / dL and an IAC range of 17-20 g / L. In addition to the adsorption property data of the examples, the table provides worst day (Day 2) diurnal breathing loss emissions performance when these examples are configured as vent-side adsorbent volumes in a Type A evaporative emission control system. The PPAV honeycombs of these examples were cylindrical in shape with a circular exterior cross-section of a measured diameter corresponding to their hydraulic diameter (equal to area / perimeter), although embodiments include PPAV honeycombs of other exterior cross-sectional shapes with cross-sectional dimensions characterized by hydraulic diameters.

[0190] [Table 2]

[0191] [Table 3]

[0192] [Table 4]

[0193] [Table 5]

[0194] [Table 6]

[0195] As can be seen from the data in Tables 2-6, the evaporative emissions control system of the present disclosure substantially reduced DBL emissions through the use of parallel channel adsorber in the vent side volume of the inventive examples compared to the use of the comparative examples. The examples in Table 2 are in the form of activated carbon PPAV honeycombs approximately 35 mm in diameter and 150 mm in length and were tested in the vent side auxiliary canister 300 of a Type A canister system as described above and in Table 1. FIG. 17 shows the carbon honeycomb comparative examples with average channel hydraulic diameters of 1.25 mm or greater and Day 2 DBL emissions of over 39 mg (open symbols, circles), which appear to plateau at hydraulic diameters between 1.8 mm and 1.25 mm. In contrast, the inventive examples having narrower channels with channel hydraulic diameters of 0.4-0.9 mm have substantially lower emissions, Day 2 emissions of less than 30 mg (closed symbols, circles). FIG. 18 shows that the lower emissions of the inventive examples correlate with a narrower cell pitch based on hydraulic diameter of 0.8-1.2 mm, especially compared to cell pitches of 1.6-2.2 mm where the higher emissions of the comparative examples appear to level off as a function of pitch.

[0196] Similarly, as shown in Figure 19, the lower emissions of the inventive examples also correlate with the channel widths of the inventive examples, about 0.4-0.9 mm, which is much smaller than the channel widths of the comparative examples, which are wider than 1.3 mm, and their cell pitches based on channel widths are also smaller, about 0.9-1.2 mm, compared to about 1.6-2 mm for the comparative examples, where the higher emissions appear to plateau as a function of pitch (Figure 20). Another way to show the effect is by cell density, where the emissions appear to plateau at about 125-240 cpsi for the comparative examples, but are substantially lower at higher cell densities for the inventive examples (Figure 21).

[0197] Surprisingly, as shown in Figure 22, the advantage in terms of canister system emissions from using the inventive examples over the comparative examples was not the result of thinner wall thickness. For example, comparative examples 1 and 17 had the same emissions of 46-47 mg despite a more than two-fold difference in cell wall thickness. Similarly, comparative examples 1 and 16 had substantially higher emissions than inventive examples 2, 4 and 7 despite wall thicknesses being in the same range of 0.27-0.42 mm.

[0198] It should be emphasized that there was no trend or correlation between the DBL emissions of the inventive examples and the macropore distribution and macropore volume properties. Referring to Tables 7-11, the macropore distribution values ​​of M / M and M / m were determined in accordance with U.S. Patent Nos. 9,322,368 and 9,174,195, respectively, which are incorporated herein by reference in their entireties. U.S. Patent Nos. 9,322,368 and 9,174,195 teach that emission control performance is optimal for a range of M / M of 30-70% and M / m of 65-150%. For example, as shown in FIG. 23, the values ​​of the various PPAV moieties in Tables 7-11 for both the comparative and inventive parts are in the same range and therefore are not a factor in the differentiated performance of the inventive examples, as are the similarities in composition, BWC, overall dimensions, and IAC. In fact, the values ​​of M / M and M / m were often outside the optimal ranges of the teachings for both groups of examples. In terms of cell wall based volumetric pore volume (normalized for differences in particle density that may result from differences in extrusion formulations), Figure 24 shows that there is no difference between the comparative and inventive examples for the volume of both small size (0.05-1 μm) and large size (1-100 μm) macropores. Approximately 20% of the wall volume (0.2 cc / cc-wall) is small size macropores, and less than 5% of the wall volume (<0.05 cc / cc-wall) is large size macropores. (Note that Example 7 is an outlier with a particularly large amount of small size macropores due to the ingredient formulation used in the pretreatment to adjust the volumetric adsorption properties to a range comparable to the other example groups in Table 7.

[0199] [Table 7]

[0200] [Table 8]

[0201] [Table 9]

[0202]

Table 10

[0203]

Table 11

[0204] In searching for the cause of the lower emissions from the inventive examples, the effect of flow restriction by the PPAV portion in the auxiliary canister was considered and found to only partially explain the complete improvement. In one set of experiments, the flow restriction of Example 1 was increased by placing an orifice plate "before" the PPAV portion of Example 1 (position "B" in FIG. 5) as Comparative Example 18, or by placing an orifice plate "after" the PPAV portion of Example 1 (position "A" in FIG. 5) as Comparative Example 19. Examples 18 and 19 were tested in the same manner as Example 1 in Table 7 and DBL emissions were measured. As shown in FIG. 25, there was some advantage of the added flow restriction for the orifice plate present in Examples 18 and 19 compared to Example 1 without an orifice plate. However, inventive Examples 2-4 and 7, which have higher cell density and smaller cell pitch, have otherwise comparable size and adsorption characteristics to Example 1, and consistently showed lower emissions, i.e. their advantage outweighs any small advantage that may be attributable to the flow restriction effect. In another experiment of the flow restriction effect, a PPAV was prepared (Example 14) with a similar 1.6 mm cell pitch size as Example 1, but with smaller parallel passage channels and thicker cell walls by using a different extrusion die, resulting in a net volumetric adsorption property similar to that of Example 1 and the other examples in Table 2. The thick wall extrusion resulted in an example with high flow restriction at the 1.6 mm cell pitch of the comparative example, but with channel widths the size of the inventive examples. As shown in Figure 25, the bleed emissions of the thick cell wall Example 14 continued the trend of slightly lower emissions than Examples 18 and 19, which suggests that the lower emissions are due to the higher flow restriction properties (especially Example 14 has lower emissions than Example 1, despite the cell walls being nearly four times thicker). Furthermore, the bleed emissions of Example 14, despite its narrow channel width, are not as low as the inventive examples with similar channel widths but narrower pitches, reinforcing the special importance of narrow cell pitch and high cell density on emissions performance (see FIG. 26).

[0205] Additional testing revealed the unexpected importance of narrow channel pitch and small hydraulic diameter for low emissions as provided by high aspect ratio shaped channels, e.g., slit-like channels, compared to some low cell pitch only and some narrow channel width only PPAV parts. A special die was used to prepare Examples 24 and 25 with 4:1 and 3:1 ratio slit-like channels (rectangular cells with long sides 4 or 3 times the length of the short side), respectively, with the short channel sides being about 1 mm long (see Tables 4 and 9). These slit-shaped channel parts were in the form of 29 mm diameter by 150 mm long monoliths with a BWC of about 4.3 g / dL. (Note: the wall thickness values ​​used to determine hydraulic diameter cell pitch were the average of x and y wall thicknesses.) The total cell density of 166-179 cpsi, as well as the cell pitch and channel width properties based on hydraulic diameter, were similar to the other comparative examples, but the cell pitch perpendicular to the short side was 1.2-1.5 mm, much shorter than the comparative examples. Similar size and BWC parts with square channels of 234 cpsi and 441 cpsi cell densities (Examples 22 and 23, respectively) were also fabricated and tested in a canister system (FIG. 27). The canister system data shows unexpectedly higher emissions for slit-shaped channel Examples 24 and 25 compared to both square channel Examples 22 and 23. The emissions trends for slit-shaped Examples 24 and 25 follow their average width-based cell pitch or hydraulic diameter cell pitch characteristics in contrast to, and despite, their narrow channel characteristics (see FIGS. 28 and 29).

[0206] There is a consistent trend for the same Type A canister system with narrower pitch examples to have lower emissions over a wide range of adsorption properties compared to examples with narrower cell pitch but otherwise comparable external dimensions and adsorption properties (BWC, IAC) for the conventional 1.6 mm cell pitch examples. Figures 30 and 31 show lower emissions over a wide range of BWC and IAC, respectively. The comparative data points for the 1.6 mm cell in these two figures have otherwise comparable examples with narrower cell pitches and include the following (Examples in Tables 2 and 3): Comparative Example 8 and Inventive Example 9 were prepared with similar dimensions of about 42 mm diameter and 142 mm length, similar cell wall thickness of about 0.3 mm, similar BWC of about 3 g / dL, and similar IAC of about 10 g / L. However, due to the narrower cell pitch (about 1 mm based on a multiple of the channel width or average channel hydraulic diameter compared to about 1.6-1.7 mm) and smaller channel openings (about 0.7 mm based on a multiple of the channel width or average channel hydraulic diameter compared to about 1.3-1.4 mm), Example 9 as the adsorption volume packing of the auxiliary canister of the Type A canister had a DBL day 2 emission of 8 mg, which was 73% lower emission compared to the emission of about 29 mg for Example 8 as the auxiliary canister adsorption volume packing. Comparative Example 10 and Inventive Example 11 were prepared using highly microporous coconut-based carbon powder instead of the mesoporous wood-based carbon powder. The resulting PPAV honeycombs had similar dimensions of about 35 mm in diameter and 150 mm in length, similar BWC of about 3 g / dL, and similar IAC of about 10 g / L. However, due to the narrower pitch (about 0.9 mm based on a plurality of channel widths or average channel hydraulic diameters compared to about 1.6-1.7 mm) and smaller channel pitch (about 0.6 mm based on a plurality of channel widths or average channel hydraulic diameters compared to about 1.3-1.4 mm), Example 11 as an adsorbent volume loading of the auxiliary canister of a Type A canister system had a DBL day 2 emission of about 17 mg, which was about half of the about 34 mg emissions generated by Example 10 as an auxiliary canister adsorbent volume loading.Comparative Examples 1 and 6 versus inventive Examples 2-5 and 7 are 35 mm x 150 mm long, have BWCs of 4.2-5.9 g / dL and IACs of 17-26 g / L (Tables 2 and 3), and have similar cell pitch, channel width, and emission comparisons and contrasts as Examples 8-11 above.

[0207] Narrower cell pitch and smaller channel width embodiments were utilized in the examples. Unexpectedly, the PPAV described herein demonstrated simpler canisters, lower flow restrictions, and lower DBL emissions. For example, Comparative Examples 12a and 12b were obtained as commercially available PPAV honeycomb NUCHAR® HCA and HCA-LBE components, approximately 29 mm in diameter and 100 mm in length, with conventional cell pitch of 1.6-1.7 mm and channel width of 1.2-1.3 mm, and were tested in combination as a series pair in a Type B canister system (Example 12a+bB) to achieve less than 20 mg of DBL day 2 emissions (12.4 mg). Canister systems have been constructed in some vehicle platforms with multiple PPAV honeycombs in series in this manner, with one part having a BWC of about 4-4.5 g / dL and another part having a BWC of less than 3 g / dL located closest to the vent of the system, to meet emissions requirements, which are especially needed in advanced engine technologies such as hybrid vehicles, GDI engines, start / stop engines, and turbo assisted engines where only small amounts of purge are available. By comparison, in an auxiliary canister of a Type B canister system, inventive Example 9B having a single PPAV honeycomb with a much narrower pitch of about 1 mm and smaller channel width and hydraulic diameter of less than 0.7 mm than either Example 12a or 12b, had emissions of 9 mg, 24% lower than the paired conventional PPAV honeycomb Example 12a+bB. Importantly, while both Examples 9B and 12a+bB had day 2 emissions of less than 20 mg DBL, Example 9B allows canister system B to further simplify the design by placing a single PPAV honeycomb, resulting in significantly reduced emissions, and also allows for a system fill flow limit of 40 slpm (1.18 kPa), 25% less than Example 12a+bB, and a system purge flow limit of 40 slpm (1.90 kPa), 22% less than Example 12a+bB, allowing for greater flexibility in canister system design choices (e.g., screens, filters, valves, tubing, etc.) that affect flow limits.

[0208] The embodiments were also tested in canister systems challenged with a wide range of purge volumes, showing consistent advantages over the narrow cell pitch and small channel width comparative examples when purge volumes were reduced. Figures 32 and 33 show consistently lower day 2 DBL emissions with inventive Example 4 compared to Comparative Example 1 when placed in a 2.1 L LEV II Type A canister system as the PPAV portion and tested over the ranges of 210-310 L and 94-138 BV (see also Table 12).

[0209] [Table 12]

[0210] Another series of experiments on the effect of purge volume on DBL emissions performance was conducted on a commercial LEV III canister system with adsorption volumes configured as shown in FIG. 8 as a Type C canister system with two PPAV honeycomb components in series on the vent side (Comparative Examples 21a and 21b, with volumes 502 and 504). In these tests, the canister system was tested as received and then retested by replacing volumes 502 and 504 with inventive PPAV honeycomb examples (Examples 20a and 20b) with equivalent external dimensions and adsorption properties (BWC and IAC) as each of the two original components as received. As shown in FIG. 34, FIG. 35 and Table 13, the results for this canister system were dramatic. For example, at higher purge conditions of 186-211 L and 71-81 BV, there was only a small difference between the emissions of the as received comparative examples and the few mg lower emissions by inventive Example 20a+bC, which is 44-47% of the results of Comparative Example 21a+bC. However, the difference becomes increasingly larger at lower purges, dropping to as low as 19% of the comparative result at 52 BV purge, with emissions of about 18 mg for Inventive Example 20a+bC compared to 97 mg for Comparative Example 21a+bC. This low level of emissions is important because the LEV III BETP emissions target is less than 20 mg for canister systems, and the prior art has noted extreme difficulty in achieving the LEV III evaporative emissions target when only less than 50-80 BV purge is available, especially in the sub-50 BV range (see U.S. Patent Application Publication No. 2011 / 0168025 Al, U.S. Patent No. 9,657,691, JSAE 20077051 / SAE 2007-01-1929, and Tank tech 2015, Trends for Fuel Subsystems (Part 1), “Low Bleed Solutions Meeting LEV III / Tier 3 Evaporative Emission Standards”, which are incorporated herein by reference in their entireties).The general belief has been that if the purge is too low, one would need to resort to more extreme measures to meet emissions, including adding heating or heat exchanger features to the canister system, or even employing a sealed fuel tank system to prevent diurnal losses. However, it is clear from these test data that by using the PPAV adsorbent volume with narrow cell pitch and small channel width described herein, it is surprisingly and unexpectedly possible to meet low emissions targets without the need for heaters or sealed tanks.

[0211] [Table 13]

[0212] Although the art teaches that higher cell densities (more cells per unit cross-sectional area or shorter cell pitch distances) in PPAV monoliths sharpen the mass transfer zone (MTZ) and more efficiently saturate the adsorption volume under dynamic flow adsorption, when applying published methods for measuring mass transfer zones for either saturation of virgin parts or saturation of parts after an adsorption purge pretreatment procedure, it was observed that there was surprisingly no such MTZ or efficiency advantage at the cell densities or cell pitches tested. Surprisingly, while the cell density and cell pitch ranges described provide benefits in DBL emissions for the inventive examples, there was no such MTZ or efficiency advantage for PPAVs tested at cell densities or cell pitches outside and within the inventive ranges described herein.

[0213] As shown by Rezaei and Webley (2009) for carbon dioxide adsorption using virgin monolith parts, the expected effect is a symmetrical pivot sharpening of the adsorbate breakthrough curve with increasing cell density, with less mass of adsorbate in the effluent before saturation. However, for n-butane adsorption, the cell density effect seems to disappear at about 200 cpsi. Valdes-Solis et al. (2004) showed a similar width of 5% to 95% breakthrough profiles comparing cell densities of 200 cpsi and 400 cpsi, corresponding to a total length of 150 mm of cut monoliths. Dynamic adsorption tests with virgin comparative examples 1 and 15-17 and inventive examples 2-4 and 7 show a sharpening of the MTZ breakthrough as the cell density increases from 30 cpsi and from a hydraulic diameter-based cell pitch of about 4 mm (example 15), but the sharpening of the MTZ gradually decreases with increasing cell density and decreasing cell pitch. An important aspect of these examples from this comparison is that the examples have approximately the same overall dimensions, BWC, and carbon feedstock properties, and differ only in cell structure, i.e., channel size and pitch. Dynamic Adsorption Efficiency (DAE) up to 95% saturation V95% ) was about 50% for Example 15, and then reached an efficiency plateau of about 60-70% at a cell density of about 200 cpsi (FIG. 36) and a cell pitch of about 2 mm (FIG. 37). Thus, the benefits of the examples in the emissions performance of the canister system according to the examples of the present invention could not have been predicted from the dynamic adsorption MTZ and efficiency behavior of the virgin parts (see Tables 14-17).

[0214] [Table 14]

[0215] [Table 15]

[0216] [Table 16]

[0217] As taught in US 2020 / 0018265, a potentially more appropriate performance predictor of PPAV monoliths for cycling applications, e.g., evaporative emission control, may be the dynamic adsorption MTZ properties after the PPAV monolith has cycled through adsorption and purge pretreatment. Applying this test to Examples 1-4, 7, and 15-17 of approximately the same outer dimensions, BWC, and carbon feedstock properties, there was a convergence of breakthrough MTZ as cell density increased from its lowest value, e.g., as cell pitch decreased from its highest value. For example, the lowest cell density PPAV had very early breakthrough and early saturation (Example 15), which was attributed to the ineffectiveness of the purge pretreatment to activate its carbon due to its wide channel width, and did not reach 95% saturation (DAE). C95% As the cell density and cell pitch increase in the examples, the DAE C95% increased to a plateau of about 55-65% with a cell density of about 200 cpsi and a cell pitch of about 2 mm (see Figures 38 and 39, respectively) without any significant dynamic adsorption efficiency behavior according to the present embodiment. Considering the simplified metric of 25% saturation (0.125 vol% n-butane outflow for 0.5 vol% inflow) described in U.S. Patent Application Publication No. 2020 / 0018265, the dynamic adsorption efficiency DAE similarly increased according to cell density (Figure 40) and cell pitch (Figure 41). C25%satThere was a plateau at 0.05C, again with no distinguishable dynamic adsorption efficiency behavior from the inventive examples. As a measure of system capacity effects, canister systems containing either the comparative examples or the inventive examples did not differ in GWC with the adsorption cycle end point caused by the cumulative breakthrough mass resulting from the vent-side PPAV volume (see FIG. 45). Thus, in effect within the canister system, the high cell density, narrow cell pitch of the vent-side PPAV portion of the system strictly affected the emissions performance of the system to which it was attached without providing any significant advantage or disadvantage to the working capacity of that system, consistent with the lack of differentiated dynamic adsorption performance of the stand-alone PPAV portion.

[0218] [Table 17]

[0219] Alternatively, the bleed-through emission components (m efl,C5% ) can be considered a possible predictor of diurnal breathing loss emissions encountered by canister systems housing PPAV moieties during BETP testing. However, such a correlation has not been evident. For example, comparing Comparative Examples 1 and 15-17 with Inventive Examples 2-4 and 7, the bleed-through mass m before 5% breakthrough was significantly greater when considered as mass (Figure 42), as a percentage of the total inflow before 95% MTZ breakthrough (Figure 43), or as a percentage of the total fill mass before 95% MTZ breakthrough (Figure 44). efl,C5%There was no clear level of , between the inventive examples and the comparative examples. Thus, the performance of the PPAV portion as an adsorbent volume component in the canister system could not be predicted from the available test methods of dynamic adsorption (see Tables 14-17). Indeed, in a special comparative test where the vapor load imposed on the vent-side PPAV was measured during the breathing loss stage of the BETP test, it actually appears that the cell density of the PPAV portion increases, increasing the challenge to the auxiliary canister housing the PPAV in a system with reduced cell pitch. In these tests using the Type A canister system, the PPAV portion was removed just before the DBL portion of the BETP protocol (in Figure 5, auxiliary canister 300 was removed) and the DBL emissions were measured. As shown in Table 18, the vapor load imposed by the main canister during the second day of the DBL portion of the BETP protocol (repeat the experiment for each example but remove auxiliary canister 300 to perform the DBL emission step of the BETP protocol) surprisingly increased almost linearly with the cell density of the PPAV portion that had been installed in the auxiliary canister during the previous preparation step. This means that the system deployed using an embodiment of the present invention provided low emissions performance for the system despite the additional vapor charge load.

[0220] [Table 18]

[0221] Without being bound by theory, one important factor is the mass transfer of the bulk phase in the PPAV monolith channels provided by the high cell density, where narrow channel dimensions appear to be advantageous. However, narrow channel width does not appear to be sufficient for the low emission effect (see Examples 14, 24 and 25). Furthermore, a second factor appears to be sufficient total open area, also provided by the high cell density, so that the velocity of gas flow through the PPAV portion is not excessive at some point in the circulation process, and sufficient residence time exists (see Example 14, where the channel width is relatively narrow, but the open area is insufficient due to conventional cell density and pitch). Nevertheless, it is clear from the examples of the invention according to the embodiments that teach how to achieve unexpectedly low bleed emissions in evaporative emission canister systems, even with very low amounts of purge. Moreover, the surprising effect on the DBL emissions of the canister system cannot be predicted by available tests of the properties and dynamic performance of the PPAV portion alone.

[0222] The contents of all references, patents, pending patent applications and published patents cited throughout this application are hereby expressly incorporated by reference.

[0223] Those skilled in the art will recognize or be able to ascertain, with no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the following claims. It should be understood that the detailed examples and embodiments described herein are provided as examples only for illustrative purposes and are not to be considered as limiting the invention in any way. Various modifications or changes in this respect will be suggested to those skilled in the art and are within the spirit and scope of this application and are considered within the scope of the appended claims. For example, the relative amounts of the components may be changed to optimize the desired effect, additional components may be added, and / or similar components may be substituted for one or more of the components described. Further advantageous features and functionality associated with the systems, methods, and processes of the present invention will become apparent from the appended claims. Moreover, those skilled in the art will recognize or be able to ascertain, with no more than routine experimentation, many equivalents to the specific embodiments of the invention described herein. Such equivalents are intended to be encompassed by the following claims. [Explanation of symbols]

[0224] 100 Evaporative Emission Control Canister System 101 Main Canister 102 Screen, Form 103 Bulkhead 104 Fuel vapor inlet 105 Vent port 106 Purge outlet Aisle 107 108 Connection hose 109 Plenum Space 201, 202, 203, 204 Absorption volume 300 Auxiliary Canister 301, 302 Absorption volume 501 Absorption volume 502, 504 PPAV Honeycomb 503 Auxiliary Canister

Claims

1. 1. An evaporative emission control canister system, comprising: One or more canisters comprising a fuel-side adsorbent volume and at least one vent-side parallel passage adsorbent volume (PPAV), the at least one vent-side PPAV comprising an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface; The parallel passages or channels have a mean channel hydraulic diameter (t ｃ，Ｄｈ ), hydraulic diameter cell pitch (CP) of 1.5 mm or less Ｄｈ ), or a combination thereof.

2. The average channel hydraulic diameter (t ｃ，Ｄｈ 2. The evaporative emission control canister system of claim 1, wherein the diameter of the canister is 1.20 mm or less (e.g., 1.10 mm or less, 1.0 mm or less).

3. The hydraulic diameter cell pitch (CP Ｄｈ 3. The evaporative emission control canister system of claim 1 or 2, wherein the diameter of the canister is 1.45 mm or less (e.g., 1.4 mm or less or 1.30 mm or less).

4. The PPAV has (i) a plurality of channel widths (t ｃ，平均 ), (ii) a cell pitch width (CP) of the multiple channels of less than about 1.5 mm ｔｃ，平均 4. The evaporative emission control canister system of claim 1, further comprising at least one of: (iii) a cell density of about 285 to about 1000 cpsi; (iv) a cell wall thickness of less than about 0.5 mm; (v) a BWC of less than about 10 g / dL; (vi) an incremental adsorption capacity of 5% to 50% n-butane at 25° C. of less than about 50 g / L; or (vii) a combination thereof.

5. The plurality of channel widths (t ｃ，平均 5. The evaporative emission control canister system of claim 4, wherein the diameter of the canister is less than about 1.20 mm (e.g., 1.10 mm or less, 1.0 mm or less).

6. The cell pitch width (CP ｔｃ，平均 6. The evaporative emission control canister system of claim 4 or 5, wherein the thickness of the canister is less than about 1.45 mm (e.g., less than about 1.4 mm, or less than about 1.3 mm).

7. The evaporative emission control canister system of any of claims 4 to 6, wherein the cell density is from about 300 to about 900 cpsi (e.g., from about 400 to about 900, or from about 400 to 800, or from about 400 to about 600).

8. The evaporative emission control canister system of any of claims 4 to 7, wherein the cell wall thickness of the PPAV is from about 0.1 mm to about 0.5 mm.

9. 9. The evaporative emission control canister system of claim 4, wherein the at least one vent side PPAV has a BWC of less than about 9.5 g / dL (e.g., less than about 9 g / dL, or less than about 6 g / dL, or from about 2.0 g / dL to about 9 g / dL).

10. The evaporative emission control canister system of any of claims 4 to 9, wherein the at least one vent side PPAV has a gram-total BWC of less than 10 g.

11. 11. The evaporative emission control canister system of any of claims 4-10, wherein the at least one vent side PPAV has an incremental adsorption capacity (IAC) of 5% to 50% n-butane at 25°C of less than 45 g / L (e.g., less than about 40 g / L, less than about 35 g / L, about 5 to about 45 g / L, about 5 to about 40 g / L, about 5 to about 35 g / L).

12. The evaporative emission control canister system of any of claims 1 to 11, wherein the at least one vent side PPAV is a honeycomb or cylindrical honeycomb structure.

13. 13. The evaporative emission control canister system of any of claims 1-12, wherein the at least one vent side PPAV comprises a sorbent material derived from at least one of wood, wood dust, wood flour, cotton linters, peat, coal, coconut, lignite, carbohydrates, petroleum pitch, petroleum coke, coal tar pitch, fruit pits, fruit stones, nut shells, nut pits, sawdust, palm, vegetables, synthetic polymers, natural polymers, lignocellulosic materials, or combinations thereof.

14. The evaporative emission control canister system of any of claims 1 to 13, wherein the at least one vent side PPAV is activated carbon or carbonized charcoal.

15. The system is operable with a purge of 315 liters or less (e.g., 300, 290, 280, 270, 260, 250, 240, 230, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, or 100 liters) applied after a 40 g / hr butane charge step as measured by the 2012 California Bleed Emissions Test Procedure (BETP), or a bed volume of 150 or less (e.g., 150, 290, 280, 270, 260, 250, 240, 230, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, or 100 liters) applied after a 40 g / hr butane charge step as measured by the 2012 California Bleed Emissions Test Procedure (BETP).

15. The evaporative emission control canister system of any of claims 1-14, having a two-day diurnal breathing loss (DBL) of 50 mg or less (e.g., 40, 30, 20, or 10 mg) at a purge of 140, 130, 120, 110, 100, 90, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, or 30 BV.

16. 1. An evaporative emissions control system comprising: a fuel tank for storing fuel; an engine having an air induction system and configured to consume fuel; One or more canisters comprising a fuel-side adsorbent volume and at least one vent-side parallel passage adsorbent volume (PPAV), the at least one vent-side PPAV comprising an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to the exterior surface, the parallel passages or channels having a mean channel hydraulic diameter (t ｃ，Ｄｈ ), hydraulic diameter cell pitch (CP) of 1.5 mm or less Ｄｈ ), or a combination thereof; and a fuel vapor inlet conduit connecting the evaporative emission control canister system to the fuel tank; a fuel vapor purge outlet conduit connecting the evaporative emission control canister system to the air induction system of the engine; and a vent conduit for venting the evaporative emission control canister system to atmosphere and for inputting purge air to the evaporative emission control canister system, the evaporative emission control canister system being formed by a fuel vapor flow path from the fuel vapor inlet conduit to the fuel side adsorbent volume toward the at least one PPAV and the vent conduit, and by an air flow path from the vent conduit to the fuel side adsorbent volume and the fuel vapor purge outlet to the at least one PPAV.

17. The average channel hydraulic diameter (t ｃ，Ｄｈ 17. The evaporative emission control canister system of claim 16, wherein the diameter of the canister is 1.20 mm or less (e.g., 1.10 mm or less, 1.0 mm or less).

18. The hydraulic diameter cell pitch (CP Ｄｈ 18. The evaporative emission control canister system of claim 16 or 17, wherein the diameter of the canister is 1.45 mm or less (e.g., 1.4 mm or less or 1.30 mm or less).

19. The PPAV has (i) a plurality of channel widths (t ｃ，平均 (ii) a cell pitch width (CP) of the multiple channels of less than about 1.5 mm ｔｃ，平均 19. The evaporative emission control canister system of any of claims 16-18, further comprising at least one of: (iii) a cell density of about 285 to about 1000 cpsi; (iv) a cell wall thickness of less than about 0.5 mm; (v) a BWC of less than about 10 g / dL; (vi) an incremental adsorption capacity of 5% to 50% n-butane at 25°C of less than about 50 g / L; or (vii) a combination thereof.

20. The plurality of channel widths (t ｃ，平均 20. The evaporative emission control canister system of claim 19, wherein the thickness of the canister is less than about 1.20 mm (e.g., 1.10 mm or less, 1.0 mm or less).

21. The cell pitch width (CP ｔｃ，平均 21. The evaporative emission control canister system of claim 19 or 20, wherein the thickness of the canister is less than about 1.45 mm (e.g., less than about 1.4 mm, or less than about 1.3 mm).

22. The evaporative emission control canister system of any of claims 19-21, wherein the cell density is from about 300 to about 900 cpsi (e.g., from about 400 to about 900, or from about 400 to 800, or from about 400 to about 600).

23. The evaporative emission control canister system of any of claims 19 to 22, wherein the cell wall thickness of the PPAV is from about 0.1 mm to about 0.5 mm.

24. 24. The evaporative emission control canister system of any of claims 19-23, wherein the at least one vent side PPAV has a BWC of less than about 9.5 g / dL (e.g., less than about 9 g / dL, or less than about 6 g / dL, or from about 2.0 g / dL to about 9 g / dL).

25. The evaporative emission control canister system of any of claims 19-24, wherein the at least one vent side PPAV has a gram-total BWC of less than 10 g.

26. 26. The evaporative emission control canister system of any of claims 19-25, wherein the at least one vent side PPAV has an incremental adsorption capacity (IAC) of 5% to 50% n-butane at 25°C of less than 45 g / L (e.g., less than about 40 g / L, less than about 35 g / L, about 5 to about 45 g / L, about 5 to about 40 g / L, about 5 to about 35 g / L).

27. The evaporative emission control canister system of any of claims 16 to 26, wherein the at least one vent side PPAV is a honeycomb or cylindrical honeycomb structure.

28. 28. The evaporative emission control canister system of any one of claims 16-27, wherein the at least one vent side PPAV comprises a sorbent material derived from at least one of wood, wood dust, wood flour, cotton linters, peat, coal, coconut, lignite, carbohydrates, petroleum pitch, petroleum coke, coal tar pitch, fruit pits, fruit stones, nut shells, nut pits, sawdust, palm, vegetables, synthetic polymers, natural polymers, lignocellulosic materials, or combinations thereof.

29. The evaporative emission control canister system of any of claims 16 to 28, wherein the at least one vent side PPAV is activated carbon or carbonized charcoal.

30. The system is configured to operate with a purge of 315 liters or less (e.g., 300, 290, 280, 270, 260, 250, 240, 230, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, or 100 liters) applied after a 40 g / hr butane charge step as measured by the 2012 California Bleed Emissions Test Procedure (BETP), or a bed volume (B 30. The evaporative emission control canister system of any of claims 16-29, having a two-day diurnal breathing loss (DBL) of 50 mg or less (e.g., 40, 30, 20, or 10 mg) at a purge of 140, 130, 120, 110, 100, 90, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, or 30 BV).

31. 1. An evaporative emission control canister system, comprising: one or more canisters including a fuel side adsorbent volume; One or more vent-side PPAVs comprising an exterior surface and a plurality of parallel passages or channels extending therethrough parallel to said exterior surface, said parallel passages or channels having a mean channel hydraulic diameter (t ｃ，Ｄｈ ), hydraulic diameter cell pitch (CP) of 1.5 mm or less Ｄｈ ), or a combination thereof; and (i) a plurality of channel widths (t ｃ，平均 ), (ii) A cell pitch width (CP) of the multiple channels of less than about 1.5 mm ｔｃ，平均 ), (iii) a cell density of about 285 to about 1000 cpsi; (iv) a cell wall thickness of less than about 0.5 mm; (v) a BWC of less than about 10 g / dL; (vi) an incremental adsorption capacity of n-butane from 5% to 50% at 25° C. of less than about 50 g / L; or (vii) one or more vent side PPAVs configured to have at least one of: the fuel side sorbent volume and the PPAV are in vapor or gas communication to form a vapor flow passage allowing air and / or fuel vapors to flow or diffuse therethrough; The evaporative emission control canister system is adapted to operate with a purge of 315 liters or less (e.g., 300, 290, 280, 270, 260, 250, 240, 230, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, or 100 liters) applied after a 40 g / hr butane charge step as measured by the 2012 California Bleed Emissions Test Procedure (BETP), or with a purge of 150 liters or less (e.g., 300, 290, 280, 270, 260, 250, 240, 230, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, or 100 liters) applied after a 40 g / hr butane charge step as measured by the 2012 California Bleed Emissions Test Procedure (BETP). An evaporative emission control canister system having a two-day diurnal breathing loss (DBL) of 50 mg or less (e.g., 40, 30, 20, or 10 mg) with a lower bed volume (BV) (e.g., 140, 130, 120, 110, 100, 90, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, or 30 BV) purge.

32. 32. The evaporative emission control canister system of any of claims 1-31, wherein the at least one vent side PPAV has an effective BWC of less than about 10 g / dL, an effective incremental adsorption capacity of 5% to 50% of n-butane at 25°C of less than about 50 g / L, or a combination thereof.

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