Low emission sorbent and tank system

Abstract

The present specification provides low DBL migration emission performance characteristics that allow for the design of a simpler and more compact evaporated fuel emission control system than those possible in the prior art by including a vent-side volume that includes a parallel channel sorbent, such as a carbon honeycomb body with narrow channel width and low cell pitch.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 001,164, filed on March 27, 2020, entitled “Low Emission Adsorbent and Canister System,” and U.S. Provisional Patent Application No. 63 / 111,768, filed on November 10, 2020, entitled “Low Emission Adsorbent and Canister System,” both of which are incorporated herein by reference in their entirety. Technical Field

[0003] 1. Field of Discovery. In various embodiments, the present invention generally relates to evaporative emission control systems. Background Art

[0004] 2. Background Information. The evaporation of gasoline fuel from a motor vehicle fuel system is a major potential source of hydrocarbon air pollution. These fuel vapor emissions occur when the vehicle is traveling, 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. Under 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.

[0005] As is well known in the art, more space-efficient activated carbon adsorbents for such concentration-swing applications are characterized by n-butane vapor adsorption isotherms with adsorption capacities that slope sharply toward high vapor partial pressures (US 6,540,815). In this way, the adsorbent has high capacity in the presence of relatively high concentrations of vapors of the type present in the presence of gasoline fuels, and the adsorbent is favorable for releasing these trapped vapors when exposed to low vapor concentrations or partial pressures, such as during purges. These high-performance activated carbons have a large amount of pore volume in the form of "small interstitial pores" (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) analysis method of nitrogen adsorption isotherms (e.g., US 5,204,310). (According to the IUPAC classification, small mesopores are pores of about 1.8 nm-2 nm size in the <2 nm micropore size range, plus pores of about 2 nm-5 nm size in the 2 nm-50 nm mesopore size range). Small mesopores are small enough to capture vapor in the condensed phase and are easily emptied when exposed to low vapor partial pressures. Therefore, the volume in these pores is linearly related to the amount of vapor that can be recovered by the adsorbent in the canister volume, called the gasoline working capacity (GWC), and is also linearly related to the ASTM butane working capacity (herein "ASTM BWC") of the adsorbent, as measured by the standard ASTM 5228 method, which is incorporated herein by reference. The ASTM BWC range of commercially available activated carbon products for this application is from about 3 to about 17 g / dL, with 9+ g / dL BWC carbons favoring working capacity for fuel vapor for canister systems, and lower BWC carbons being used in one or more subsequent volumes (i.e., vent side adsorbent volumes) for the atmospheric orifice or vent side. In general, cylindrical pellets and other engineered shapes (e.g., spherical particles) of activated carbon are preferred over irregularly shaped or crushed particles, especially for tank systems requiring regulated flow restrictions, such as for vapor capture during refueling. Advantages of pelletized and engineered shapes of activated carbon include good mechanical strength, low dust, low dusting, high on-size yield in handling, and narrow particle size distribution that provides consistency in liter-size tank fills after bulk shipping and handling.

[0006] Although highly mesoporous adsorbents are advantageous for working capacity, the high ASTM BWC of the adsorbent and its high GWC appear in practice to run counter to the simultaneous need for a fuel vapor emission control system to provide low emissions even when the vehicle is not operating.

[0007] For example, the increase in environmental concerns continues to drive strict regulations on 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, causing the vapor pressure in the fuel tank to increase. Typically, in order to prevent fuel vapor from leaking from the vehicle into the atmosphere, the fuel tank is connected to a canister containing a suitable fuel adsorbent material through a conduit, which can temporarily adsorb fuel vapor. The canister defines a vapor or fluid material flow path so that when the vehicle is stationary, the fuel vapor of the fluid passes from the fuel tank through the fuel tank conduit, through one or more adsorbent volumes, and reaches a vent 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, wherein the fuel vapor is adsorbed in a temporary storage and the purified air is released into the atmosphere through the vent of the canister. Once the engine is started, ambient air is drawn into the canister system through the vent of the canister. The purge air flows through the adsorbent volume inside the canister and desorbs the fuel vapor adsorbed on the adsorbent volume, and then enters the internal combustion engine through the fuel vapor purge conduit. The purge air is unable to desorb all of the fuel vapor adsorbed on the adsorbent volume, resulting in residual hydrocarbons ("residues") that may be emitted to the atmosphere.

[0008] In addition, the residual material in local equilibrium with the gas phase also allows fuel vapor to migrate from the fuel tank through the canister system in the form of emissions. Such emissions typically occur when the vehicle has been parked and is subject to diurnal temperature changes over a period of several days, and are generally referred to as "diurnal ventilation loss" (DBL) emissions. The California Low Emission Vehicle Regulations require these DBL emissions from the canister system of many vehicles starting with the 2003 model year to be less than 10 mg ("PZEV"), and a large number of vehicles starting with the 2004 model year to be less than 50 mg, and typically less than 20 mg ("LEV-II").

[0009] Currently, California Low Emission Vehicle regulations ("LEV-III") and United States Federal Tier 3 regulations require that canister DBL emissions not exceed 20 mg according to the permeation emissions test procedure (BETP), as written in California Evaporative Emissions Standards and Test Procedures for 2001 and Subsequent Model Motor Vehicles, March 22, 2012. In addition, regulations regarding DBL emissions continue to pose challenges to evaporative emission control systems, especially when the amount of purge air is low. For example, the DBL emission potential may be more severe for hybrid vehicles, which include vehicles whose powertrains are an internal combustion engine and an electric motor ("HEV"), and vehicles with a start-stop system that automatically shuts down and restarts the internal combustion engine to reduce the amount of engine idling time, thereby reducing fuel consumption and tailpipe emissions. In such hybrid vehicles, the internal combustion engine may be off for almost half of the time during vehicle operation. Because the fuel vapor adsorbed on the adsorbent is purged only when the internal combustion engine is operating, the adsorbent in the canister of a hybrid vehicle is purged with fresh air for less than half the time of a conventional vehicle and is typically in the range of 55 bed volumes (BV) to 100 BV (based on the U.S. EPA Federal Test Procedure (FTP)-75 driving cycle), where "BV" is the ratio of the total volume of the purge flow to the volume of the adsorbent in the canister system. Moreover, hybrid vehicles produce almost the same amount of evaporated fuel vapor as conventional vehicles. The lower purge frequency and lower purge volume of hybrid vehicles are insufficient to clean the residual hydrocarbon residues of the adsorbent in the canister, causing high DBL emissions. Other power systems also face similar challenges of providing high purge volumes for refreshing the canister and providing the optimal air-fuel mixture and ratio to the engine when engineered to achieve optimal driving performance, fuel efficiency, and tailpipe emissions. These power systems include turbocharged or turbo-assisted engines and gasoline direct injection ("GDI") engines.

[0010] In order to meet evaporative fuel emission regulatory standards during the vehicle design phase, vehicle manufacturers typically provide potential suppliers with target specifications for overall canister system performance, including functional contents, appearance, physical properties, and durability, thereby leaving appropriate design flexibility for canister system manufacturers to achieve these goals. For example, General Motors has set a number of design specifications for evaporative emission control canister systems (see GMW16494). One notable specification is the total allowable pressure drop for the carbon canister system. In this example, the maximum flow restriction for a canister system for an onboard refueling vapor recovery device (ORVR) "shall be 0.90 ± 0.225 kPa at 60 liters per minute (lpm) air flow... as measured at the tank pipe as air flows from the canister tank pipe to the fresh air pipe" (see GMW-16494 Section 3.2.1.3.2.2). This specification and other specifications in GMW-16494 provide examples of the extent of flow restriction allowed by vehicle manufacturers.

[0011] Because of this specification, canister system designers consider a wide variety of chamber designs and adsorbent options because, in addition to the different fuel emission regulations around the world, different vehicle platforms from different vehicle manufacturers have very different requirements for engine type, engine operating design, space availability, purge availability, and canister system control strategies. Of course, "one size does not fit all" when it comes to canister system design and its adsorbent filling.

[0012] In order to meet the apparently opposing needs of high working capacity and low DBL emission performance, several methods have been reported. One method is to significantly increase the volume of the purge gas to enhance the desorption of residual hydrocarbon residues from the adsorbent volume. . See U.S. Patent No. 4,894,072. However, this method has the following disadvantages: it complicates the management of the fuel / air mixture of the engine during the purge step and tends to adversely affect tail pipe emissions, and such high purge volumes are completely unavailable for certain power system designs. Considering the design and installation costs, an auxiliary pump can be used at a certain location within the evaporative emission control system to supplement, assist or enhance the purge flow or volume, such as a component for supplementing the engine vacuum and avoiding some problems of engine performance and tail pipe emission control that occur when relying solely on engine vacuum.

[0013] Another approach is to design the tank with a relatively small cross-sectional area on the vent side of the tank, either by resizing the existing tank or by installing an appropriately sized supplemental vent side tank cavity. This approach reduces residual hydrocarbon residue by increasing the strength of the purge air. One disadvantage of this approach is that the relatively small cross-sectional area makes the tank system excessively flow restrictive. See U.S. Pat. No. 5,957,114.

[0014] Another method to improve the purge efficiency is to heat the purge air, or to have a portion of the adsorbent volume with adsorbed fuel vapor, or both. However, this method increases the complexity of control system management and brings some safety hazards. See U.S. Patent Nos. 6,098,601 and 6,279,548.

[0015] Another approach is to direct the fuel vapor through a fuel-side adsorbent volume located near the fuel source in the fluid stream, and then through at least one subsequent (i.e., vent-side) adsorbent volume located downstream of the fuel-side adsorbent before discharge to the atmosphere, wherein the fuel-side adsorbent volume (herein, the initial adsorbent volume) has a higher isotherm slope than the subsequent (i.e., vent-side) adsorbent volume, defined as the incremental adsorption capacity. See U.S. Pat. No. RE38,844, which is incorporated herein by reference in its entirety.

[0016] Another approach, particularly useful when only low purge amounts may be available, is to direct the fuel vapor through at least one subsequent (i.e., vent side) adsorbent that contains a window of increasing adsorption capacity (volume-averaged ASTM BWC, a specific gram-total BWC capacity) and / or a substantially uniform structure that promotes substantially uniform air and vapor flow distribution across its flow path cross-section. See U.S. 9,732,649 and U.S. 10,960,342, both of which are incorporated herein by reference in their entirety.

[0017] One effective form of subsequent adsorbent volume with lower incremental adsorption capacity toward the vent side of the canister system is an elongated cylindrical ceramic-bonded activated carbon honeycomb such as HCA or HCA-LBE (Ingevity, North Charleston, South Carolina, USA), are typically available in diameters of 29 mm, 35 mm, and 41 mm and in specific lengths between 50 mm and 200 mm. The internal parallel channel structure is a square grid with about 200 cells per square inch (cpsi), with a cell wall thickness of about 0.3 mm. These design components are expensive to manufacture and require special techniques and equipment to manufacture. Care must be taken to precisely control the composition characteristics, formulation, mixing, extrusion, heat treatment, and cutting to meet the final product specifications of mechanical strength, adsorption capacity, and flow restriction. The finished adsorbent components must be durable, defect-free, and dimensionally accurate, and they must perform emission control during the actual life of the vehicle. Although quite effective as a ventilation side adsorbent volume filler to control diurnal ventilation loss emissions, for some fuel systems, these ceramic bonded honeycombs require larger size components and multiple components in series to meet emission control targets. Even at very low purge levels, the honeycomb may still fail to meet emission control targets, resulting in the use of very expensive sealed tank fuel systems.

[0018] Therefore, new adsorbent options and approaches that balance tradeoffs in cost, size, flow restriction, operating capacity, diurnal air change loss (DBL) performance, complexity, and placement flexibility are urgently needed. For example, it is desirable to have a higher performance adsorbent honeycomb that can allow for a smaller and simpler approach to system design and operation when both normal or low levels of purge are available. Summary of the invention

[0019] The present invention describes an adsorbent material in the form of a parallel path adsorbent volume (PPAV) and methods of using the same, which is configured to provide surprising and unexpected low DBL permeation emissions performance when incorporated into a vehicle emission canister system, an evaporative emission control canister system. The PPAV advantageously allows the design of simpler and more compact evaporative fuel emission control systems than those currently known or available. As described herein, when tested under a standard vapor cycle regimen, using a standard permeation emissions test procedure such as the BETP as written in California Evaporative Emissions Standards and Test Procedures for 2001 and Subsequent Model Motor Vehicles, March 22, 2012, an evaporative emission control canister system including a PPAV as described herein shows significantly lower emissions.

[0020] Thus, in one aspect, the present specification provides a PPAV comprising an outer surface and a plurality of parallel channels or channels extending therethrough parallel to the outer surface, and wherein the parallel channels or channels are configured to have an average channel hydraulic diameter (referred to herein as "tc,Dh ”), hydraulic diameter unit spacing less than 1.5 mm (referred to herein as “CP Dh ”) or at least one of a combination thereof. As detailed herein, when incorporated into an evaporative emission system, the PPAV described herein surprisingly and unexpectedly results in reduced DBL permeation emissions while providing a less complex design.

[0021] In another aspect, the present specification provides an evaporative emission control canister system comprising one or more canisters, the one or more canisters comprising a fuel side adsorbent volume and at least one vent side parallel channel adsorbent volume (PPAV), wherein the at least one vent side PPAV comprises an exterior surface and a plurality of parallel channels or channels extending therethrough parallel to the exterior surface, and wherein the parallel channels or channels are configured to have an average channel hydraulic diameter (t ) less than or equal to 1.25 mm. c,Dh ), hydraulic diameter unit spacing (CP) less than or equal to 1.5 mm Dh ) or at least one of a combination thereof. In other aspects or embodiments described herein, the specification provides an evaporative emission control system, the evaporative emission control system comprising: a fuel tank for storing fuel; an engine having an air induction system and adapted to consume the fuel; and one or more canisters comprising a fuel-side adsorbent volume and at least one vent-side PPAV, wherein the at least one vent-side PPAV comprises an outer surface and a plurality of parallel channels or channels extending therethrough parallel to the outer surface, and wherein the parallel channels or channels are configured to have an average channel hydraulic diameter (t less than or equal to 1.25 mm). c,Dh ) and a hydraulic diameter unit spacing (CP) less than or equal to 1.5 mm Dh ) or at least one of a combination thereof, and

[0022] wherein the canister includes a fuel vapor inlet conduit connecting the evaporative emission control canister system to the fuel tank;

[0023] a fuel vapor purge outlet conduit connecting the evaporative emission control canister system to an air induction system of the engine; and

[0024] a vent conduit for venting the evaporative emission control canister system to atmosphere and for allowing purge air to enter 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 toward the at least one PPAV and the vent conduit to the fuel side adsorbent volume, and by an air flow path from the vent conduit toward the fuel side adsorbent volume and the fuel vapor purge outlet to the at least one PPAV.

[0025] In any aspect or embodiment described herein, the evaporative emission control canister system has a two-day diurnal ventilation loss (DBL) of no more than 50 mg at no more than 315 liters of purge or no more than 150 bed volumes (BV) applied after the 40 g / hr butane loading step as determined by the 2012 California Bleed Emissions Test Procedure (BETP).

[0026] In any aspect or embodiment described herein, the PPAV comprises an adsorbent material selected from the group consisting of activated carbon, charcoal, zeolite, clay, porous polymer, porous alumina, porous silica, molecular sieves, kaolin, titania, cerium oxide, metal organic frameworks, and combinations thereof.

[0027] In any aspect or embodiment described herein, the shaped PPAV adsorbent material comprises activated carbon derived from a material comprising a member selected from the group consisting of wood, wood chips, 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, and combinations thereof. In any aspect or embodiment described herein, the shaped PPAV adsorbent material comprises activated carbon derived from at least one of wood, wood chips, 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.

[0028] In any of the embodiments described herein, the evaporative emission control system may further include a heating unit.

[0029] In another aspect, the present description provides a method for reducing fuel vapor emissions in an evaporative emission control system, the method comprising contacting fuel vapor with an evaporative emission control system as described herein comprising a PPAV as described herein.

[0030] The aforementioned general practical fields are given for example only, and are not intended to limit the scope of the present disclosure and the appended claims. According to the claims, descriptions and examples of the present invention, those of ordinary skill in the art will understand the additional goals and advantages associated with the compositions, methods and processes of the present invention. For example, various aspects and embodiments of the present invention can be utilized in numerous combinations, all of which are explicitly considered by this specification. These additional advantage goals and embodiments are explicitly included in the scope of the present invention. Publications and other materials used herein to illustrate the background of the present invention and to provide additional details about practice in certain circumstances are incorporated by reference. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings, which are incorporated into and constitute a part of this specification, illustrate several embodiments of the present invention and, together with the specification, are used to explain the principles of the present invention. The accompanying drawings are only for the purpose of illustrating embodiments of the present invention and should not be construed as limiting the present invention. Additional objects, features and advantages of the present invention will become apparent from the following detailed description in conjunction with the accompanying drawings, which illustrate exemplary embodiments of the present invention, in which:

[0032] Figure 1 is a cross-sectional view of an exemplary evaporative emission control canister system (100) described herein.

[0033] Figure 2 is a cross-sectional view of an exemplary evaporative emission control canister system (100) described herein.

[0034] Figure 3 is a cross-sectional view of an exemplary evaporative emission control canister system (100) as described herein, which includes four adsorbent volumes (201, 202, 203, and 204) in a main canister, and an auxiliary canister (300) including a subsequent adsorbent volume (301) therein.

[0035] Figure 4 is a cross-sectional view of an exemplary evaporative emission control canister system (100) as described herein, which includes four adsorbent volumes (201, 202, 203, and 204) in a main canister, and an auxiliary canister (300) including two subsequent adsorbent volumes (301, 302) therein.

[0036] Figure 5 is a cross-sectional view of an exemplary evaporative emission control canister system (100) showing a system for measuring DBL emission performance of comparative and inventive embodiments, including three adsorbent volumes (501, 203, 204) in a main canister when a single PPAV honeycomb (502) is present in an auxiliary vent side canister (300).

[0037] Figure 6 is a cross-sectional view of an exemplary evaporative emission control canister system (100) showing the system for measuring DBL emissions performance of comparative and inventive embodiments when only two adsorbent volumes (501, 202) are present in the main canister and one PPAV honeycomb (502) is present in the auxiliary vent side canister (300).

[0038] Figure 7is a cross-sectional view of an exemplary evaporative emission control canister system (100) showing the system for measuring DBL emissions performance of comparative and inventive embodiments when only two adsorbent volumes (501, 202) are present in the main canister and two PPAV honeycombs (502, 504) are present in the auxiliary vent side canisters (300, 503) in series.

[0039] Figure 8 is a cross-sectional view of an exemplary evaporative emission control canister system (100) showing the system for measuring DBL emissions performance of comparative and inventive embodiments when 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.

[0040] Fig. 9 is a diagram showing cross-sectional features of a honeycomb-based PPAV as described herein, and shows the cell wall thickness (t w ), channel width (t c ), channel area (A c ), channel perimeter length (P c ) and surface thickness (t s ).

[0041] Fig.10 is a graph showing four rotations from which the outer diameter (D) of an exemplary honeycomb-shaped PPAV was measured in both caliper and image analysis measurements. o ).

[0042] Fig.11 is a diagram showing four rotations from which the inner diameter (D) of an exemplary honeycomb-shaped PPAV is measured in an image analysis measurement. i ).

[0043] Fig.12 is a diagram showing vertical and horizontal crosshairs from which the median channel width and wall thickness (t c,m and t w,m ) and the base channel width and wall thickness (t c,b and t w,b ).

[0044] Fig.13 is a diagram showing an n by n ("nxn") square cell grid from which nxn grid channel widths (t c,nxn ) and nxn wall thickness (t c,m and tw,nxn ).

[0045] Fig.14 is a graphical representation of the effluent concentration response characteristics for unused PPAV during initial saturation according to the Dynamic Butane Adsorption Capacity Test. The efficiency is the cumulative mass fraction (shaded area) adsorbed relative to the cumulative influent mass up to the saturation point (eg, 95%).

[0046] Fig.15 is a graphical representation of the effluent concentration response characteristics of a cycled PPAV during the saturation step following the initial saturation and purge steps according to a dynamic butane adsorption capacity test. For the PPAV that passed through the previous adsorption and purge cycle, MTZ breakthrough also occurred. In addition, residual residues from incomplete adsorbate removal from the previous purge step resulted in breakthrough of the adsorbate in the effluent before MTZ breakthrough.

[0047] Fig.16 is a graphical representation of the effluent concentration response characteristics of a cyclic PPAV during the saturation step following the initial saturation and purge steps according to a dynamic butane adsorption capacity test for an intermediate breakthrough point of 25% of a 0.5 vol% influent butane concentration.

[0048] Fig.17 is the average channel hydraulic diameter of PPAV (t c,Dh ) as a function of DBL discharge on the second day for a comparative example (open circles) and an inventive example (filled circles) of 35 mm diameter x 150 mm length.

[0049] Fig.18 It is used as the hydraulic diameter unit spacing of PPAV channel (CP Dh ) as a function of DBL discharge on the second day for a comparative example (open circles) and an inventive example (filled circles) of 35 mm diameter x 150 mm length.

[0050] Fig.19 is a multiple of the PPAV channel width (t c,avg ) as a function of DBL discharge on the second day for a comparative example (open circles) and an inventive example (filled circles) of 35 mm diameter x 150 mm length.

[0051] Fig. 20 It is a PPAV cell pitch (CP tc,avg ; i.e., test data of the 35 mm diameter x 150 mm length comparative example (open circles) and the inventive example (filled circles) for the 2nd day DBL discharge as a function of “multiple width cell spacing”).

[0052] Fig.21Test data for the 35 mm diameter x 150 mm length comparative example (open circles) and the inventive example (filled circles) at day 2 DBL discharge as a function of PPAV cell density (cells per square inch; cpsi).

[0053] Fig. 22 is the PPAV unit wall thickness (t w,avg ) as a function of DBL discharge on the second day for a comparative example (open circles) and an inventive example (filled circles) of 35 mm diameter x 150 mm length.

[0054] Fig.23 Test data for 35 mm diameter x 150 mm length comparative examples (open circles and open squares) and inventive examples (closed circles and closed squares) of macrovoid ratio (M / M and M / m) as a function of cell density (cells per square inch; cpsi) are shown.

[0055] Fig.24 Test data for 35 mm diameter x 150 mm length comparative examples (open circles and open squares) and inventive examples (closed circles and closed squares) are shown as a function of macropore volume (PV) as a function of cell density (cells per square inch; cpsi).

[0056] Fig.25 Test data for a 35 mm diameter x 150 mm length comparative example (open circles) and an inventive example (filled circles) for day 2 DBL discharge as a function of PPAV flow restriction at 40 lpm (kPa).

[0057] Fig.26 is the average channel hydraulic diameter of PPAV (t c,Dh ) as a function of DBL discharge on the second day for a comparative example (open circles) and an inventive example (filled circles) of 35 mm diameter x 150 mm length.

[0058] Fig. 27 Test data for the 29 mm diameter x 150 mm length comparative example (open diamonds) and inventive example (filled diamonds) and PPAV with slot-shaped cells (filled rectangles) for DBL discharge on day 2 as a function of PPAV cell density (cells per square inch; cpsi).

[0059] Fig.28 is the spacing of PPAV units based on hydraulic diameter (CP Dh) for the 2nd day DBL discharge as a function of ) for the 29 mm diameter x 150 mm length comparative example (open diamonds) and the inventive example (solid diamonds) and the PPAV with a slit-shaped cell (solid rectangles).

[0060] Fig.29 It is a PPAV cell pitch (CP tc,avg ) or test data of 29 mm diameter x 150 mm length comparative example (open diamonds) and invention example (solid diamonds) for the 2nd day DBL discharge as a function of cell spacing for the slit-shaped cell embodiment based on narrow channel width, and PPAV (solid rectangles) with slit-shaped cells.

[0061] Fig.30 Test data for the Comparative Example (open circles) and the Inventive Example (closed circles) on Day 2 DBL emissions as a function of PPAV BWC (g / dL) are shown.

[0062] Fig.31 Test data for the Comparative Example (open circles) and the Inventive Example (closed circles) are shown for Day 2 DBL emissions as a function of PPAV IAC (g / L-bed).

[0063] Fig.32 Test data for the Comparative Example (open circles) and the Inventive Example (closed circles) are shown for Day 2 DBL emissions as a function of liters of purge volume (L) for the Comparative Example (open circles) and the Inventive Example (closed circles).

[0064] Fig.33 Test data for the Comparative Example (open circles) and the Inventive Example (closed circles) are plotted as a function of purge bed volume (BV) for the Day 2 DBL discharge.

[0065] Fig.34 Test data for the Comparative Example (open circles) and the Inventive Example (closed circles) on Day 2 DBL discharge as a function of liters of purge volume (L) are shown.

[0066] Fig.35 Test data for the Comparative Example (open circles) and the Inventive Example (closed circles) are plotted as a function of purge bed volume (BV) for the Day 2 DBL discharge.

[0067] Fig.36 is the adsorption efficiency (DAE) of the unused part as a function of cell density (cells per square inch; cpsi) V95％ ) of the comparative example (hollow circles) and the inventive example (solid circles).

[0068] Fig.37 is the unit spacing based on hydraulic diameter (CPDh ) as a function of the unused component adsorption efficiency (DAE V95％ ) of the comparative example (hollow circles) and the inventive example (solid circles).

[0069] Fig.38 is the cycle component adsorption efficiency (DAE) as a function of cell density (cells per square inch; cpsi) C95％ ) of the comparative example (hollow circles) and the inventive example (solid circles).

[0070] Fig.39 is the unit spacing based on hydraulic diameter (CP Dh ) is a function of the cycle component adsorption efficiency (DAE) C95％ ) of the comparative example (hollow circles) and the inventive example (solid circles).

[0071] Fig.40 is the cycle component adsorption efficiency (DAE) as a function of cell density (cells per square inch; cpsi) C0.125体积％ ) of the comparative example (hollow circles) and the inventive example (solid circles).

[0072] Fig.41 is the unit spacing based on hydraulic diameter (CP Dh ) is a function of the cycle component adsorption efficiency (DAE) C0.125体积％ ) of the comparative example (hollow circles) and the inventive example (solid circles).

[0073] Fig.42 Test data for 35 mm diameter x 150 mm length comparative examples (open circles) and inventive examples (filled circles) at day 2 DBL discharge as a function of PPAV permeate mass (g) before 5% BT.

[0074] Fig.43 Test data for a 35 mm diameter x 150 mm long comparative example (open circles) and an inventive example (filled circles) of day 2 DBL discharge as a function of PPAV percent influent relative to permeation of total butane delivered prior to 95% BT.

[0075] Fig.44 Test data for 35 mm diameter x 150 mm long comparative examples (open circles) and inventive examples (filled circles) at day 2 DBL discharge as a function of PPAV penetration relative to total mass adsorbed prior to 95% BT.

[0076] Fig.45Test data for 35 mm diameter x 150 mm length comparative examples (open circles) and inventive examples (filled circles) are shown for gasoline working capacity (g) as a function of PPAV cell density (cells per square inch; cpsi).

[0077] Fig.46 Illustration of the x-axis and y-axis orientations applied to image analysis of a PPAV component having a slit-shaped cell. DETAILED DESCRIPTION

[0078] The present disclosure will now be described more fully below, but all embodiments of the present disclosure are not shown. Although the present disclosure has been described in conjunction with exemplary embodiments, it will be appreciated by those skilled in the art that various changes may be made and elements thereof may be replaced with equivalents without departing from the scope of the present disclosure. In addition, many modifications may be made without departing from the substantive scope of the present disclosure to adapt specific structures or materials to the teachings of the present disclosure.

[0079] In the case of providing a range of values, it should be understood that each intermediate value between the upper and lower limits of the range and any other described or intermediate values ​​in the described range are included in the present invention. The upper and lower limits of these smaller ranges can be independently included in a smaller range and are also encompassed in the present invention, subject to any specific exclusion limits in the described range. In the case where the described range includes one or two limits, the present invention also includes the scope of excluding any two of the included limits.

[0080] The following terms are used to describe the present invention. Where a term is not specifically defined herein, that term is given the art-recognized meaning by those of ordinary skill in the art when that term is used in the context of describing the present invention.

[0081] As used herein and in the appended claims, the articles "a" and "an" are used herein to refer to one or more than one (ie, at least one) of the grammatical object of the article unless the context clearly dictates otherwise. For example, "an element" means one element or more than one element.

[0082] As used herein in the specification and claims, the phrase "and / or" should be understood to mean "either or both" of the elements so combined, i.e., elements that are present in combination in some cases and separately in other cases. Multiple elements listed with "and / or" should be interpreted in the same manner, i.e., "one or more" elements so combined. In addition to the elements specifically identified by the "and / or" clause, other elements may optionally be present, whether related or unrelated to those specifically identified. Thus, as a non-limiting example, a reference to "A and / or B", when used in conjunction with open language such as "comprising", may refer to A only (optionally including elements other than B) in one embodiment; to B only (optionally including elements other than A) in another embodiment; to A and B (optionally including other elements) in yet another embodiment; and so on.

[0083] 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 the items in a list, "or" or "and / or" should be interpreted as inclusive, i.e., including at least one, but also including more than one of many elements or lists of elements, and optionally, items that are not listed in addition. Only when the opposite term is clearly indicated, such as "only one" or "exactly one", or, when used in the claims, "consisting of..." refers to exactly one element of many elements or lists of elements. In general, when preceded by exclusive terms such as "either", "one of", "only one" or "exactly one", as used herein, the term "or" should only be interpreted as indicating exclusive alternatives (i.e., "one or the other but not both").

[0084] In the claims and the foregoing description, all transitional phrases, such as "comprising," "including," "carrying," "having," "containing," "involving," "holding," "consisting of," and the like, should be understood as open-ended, i.e., meaning including, but not limited to. Only the transitional phrases "consisting of" and "consisting essentially of" should be closed or semi-closed transitional phrases, respectively, as described in Section 2111.03 of the 10 United States Patent Office Manual of Patent Examining Procedures.

[0085] As used herein in the specification and claims, referring to a list of one or more elements, the phrase "at least one" should be understood to mean at least one element selected from any one or more elements in the list of elements, but does not necessarily include at least one of each and every element specifically listed in the list of elements, and does not exclude any combination of elements in the list of elements. This definition also allows that in addition to the elements specifically identified within the list of elements referred to by the phrase "at least one", there may be optionally present elements, whether related or unrelated to those elements specifically identified. Thus, as a non-limiting example, in one embodiment, "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") may refer to at least one, optionally including more than one A, without B (and optionally including elements other than B); in another embodiment, to at least one, optionally including more than one B, without A (and optionally including elements other than A); in yet another embodiment, to at least one, optionally including more than one A, and at least one B, optionally including more than one B (and optionally including other elements); and so on. It should also be understood that in any method claimed herein that includes more than one step or action, the order of the steps or actions of the method is not necessarily limited to the order in which the steps or actions of the method are recited unless clearly indicated to the contrary.

[0086] As used herein, the phrase "less than" (e.g., less than about 2) or "less than or equal to" (e.g., less than or equal to about 2) followed by a particular number refers to a non-zero number that is less than the stated number or a non-zero number that is less than or equal to the stated number, respectively.

[0087] As used herein, the terms "fluid," "gas" or "gaseous," and "vapor" or "vapor" are used in a generic sense and are intended to be interchangeable unless the context dictates otherwise.

[0088] Described herein are parallel channel adsorbent volume (PPAV) articles (referred to herein as "shaped PPAVs" or "PPAVs") and evaporative emission control canister systems including the same that surprisingly and unexpectedly exhibit reduced diurnal ventilation loss (DBL) emissions due to the PPAV being positioned toward the vent side of the system. As used herein, unless the context indicates otherwise, a PPAV refers to a single article or component (i.e., a nominal volume), wherein the PPAV includes an adsorbent material and has an exterior surface and a plurality of parallel channels or channels extending therethrough parallel to the exterior surface, and wherein the parallel channels or channels are configured as described herein.

[0089] Thus, in one aspect, the present specification provides a PPAV comprising an outer surface and a plurality of parallel channels or channels extending therethrough parallel to the outer surface, and wherein the parallel channels or channels are configured to have an average channel hydraulic diameter (t c,Dh ), hydraulic diameter unit spacing (CP) less than 1.5 mm Dh ) or at least one of a combination thereof. As detailed herein, when incorporated into an evaporative emission system, the PPAV described herein surprisingly and unexpectedly results in reduced DBL permeation emissions while providing a less complex design.

[0090] In any aspect or embodiment described herein, 4A is calculated as described herein c / P c The average channel hydraulic diameter of PPAV (t c,Dh ) are independently selected from, for example, less than or equal to 1.25 mm, less than or equal to 1.20 mm, less than or equal to 1.10 mm, less than or equal to 1.0 mm; or selected from 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 selected from 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 1.1 5mm, about 0.2mm to about 1.1mm, about 0.2mm to about 1.0mm, about 0.3mm to about 1.25mm, about 0.3mm to about 1.20mm, about 0.3mm to about 1.15mm, about 0.3mm to about 1.1mm, about 0.3mm to about 1.0mm, about 0.4mm to about 1.25mm, about 0.4mm to about 1.20mm, about 0.4mm to about 1.15mm, about 0.4mm to about 1.1mm, about 0.4mm to about 1.0mm, about 0.4mm to about 0.95mm, about 0.4mm to about 0.9mm, and including all subranges and combinations thereof.

[0091] In any aspect or embodiment described herein, the average channel hydraulic diameter (t c,Dh ) plus average wall thickness (t w,avg ) and the hydraulic diameter unit spacing (CP Dh) are independently selected from, for example, less than 1.50 mm, less than 1.40 mm, or less than 1.30 mm; or from about 0.5 mm to about 1.5 mm, or from about 0.5 mm to about 1.4 mm, or from about 0.5 mm to about 1.3 mm, or from about 0.5 mm to about 1.2 mm, or from about 0.6 mm to about 1.5 mm, or from about 0.6 mm to about 1.4 mm, or from about 0.6 mm to about 1.3 mm, or from about 0.6 mm to about 1.2 mm, or from about 0.7 mm to about 1.5 mm, or from about 0.7 mm to about 1.4 mm, or from about 0.7 mm to about 1.3 mm, or from about 0.7 mm to about 1.2 mm, or from about 0.8 mm to about 1.5 mm, or from about 0.75 mm to about 1.4 mm, or from about 0.75 mm to about 1.3 mm, or from about 0.75 mm to about 1.2 mm, and including all subranges and combinations thereof.

[0092] In another aspect, the present specification provides an evaporative emission control canister system comprising one or more canisters, the one or more canisters comprising a fuel side adsorbent volume and at least one vent side parallel channel adsorbent volume (PPAV), wherein the at least one vent side PPAV comprises an exterior surface and a plurality of parallel channels or channels extending therethrough parallel to the exterior surface, and wherein the parallel channels or channels are configured to have an average channel hydraulic diameter (t ) less than or equal to 1.25 mm. c,Dh ), hydraulic diameter unit spacing (CP) less than or equal to 1.5 mm Dh ) or at least one of their combinations.

[0093] In certain aspects, the present specification provides an evaporative emission control canister system comprising one or more canisters having a plurality of chambers, each chamber defining a volume, the plurality of chambers being fluidly connected to allow fluid or vapor to flow directly from one chamber to the next chamber, and a chamber proximate a fuel vapor inlet (i.e., a fuel port or a fuel tank port) comprising a fuel-side adsorbent volume, and a chamber proximate a vent port comprising a vent-side parallel channel adsorbent volume (PPAV), wherein at least one vent-side PPAV comprises an exterior surface and a plurality of parallel channels or channels extending therethrough parallel to the exterior surface, and wherein the parallel channels or channels are configured to have an average channel hydraulic diameter (t) less than or equal to 1.25 mm. c,Dh ), hydraulic diameter unit spacing (CP) less than or equal to 1.5 mm Dh ) or at least one of their combinations.

[0094] In other aspects or embodiments described herein, the specification provides an evaporative emission control system comprising: a fuel tank for storing fuel; an engine having an air induction system and adapted to consume the fuel; and one or more canisters comprising a fuel-side adsorbent volume and at least one vent-side PPAV, wherein the at least one vent-side PPAV comprises an outer surface and a plurality of parallel channels or channels extending therethrough parallel to the outer surface, and wherein the parallel channels or channels are configured to have an average channel hydraulic diameter (t less than or equal to 1.25 mm). c,Dh ) and a hydraulic diameter unit spacing (CP) less than or equal to 1.5 mm Dh ) or at least one of a combination thereof, and

[0095] wherein the canister includes a fuel vapor inlet conduit connecting the evaporative emission control canister system to the fuel tank;

[0096] a fuel vapor purge outlet conduit connecting the evaporative emission control canister system to an air induction system of the engine; and

[0097] a vent conduit for venting the evaporative emission control canister system to atmosphere and for allowing purge air to enter the evaporative emission control canister system, wherein the evaporative emission control canister system is defined by a fuel vapor flow path from a fuel vapor inlet conduit toward the at least one PPAV and the vent conduit to a fuel side adsorbent volume, and by an air flow path from the vent conduit toward the fuel side adsorbent volume and a fuel vapor purge outlet to the at least one PPAV.

[0098] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, the average channel hydraulic diameter (t c,Dh) are independently selected from, for example, less than or equal to 1.25 mm, less than or equal to 1.20 mm, less than or equal to 1.10 mm, less than or equal to 1.0 mm; or selected from 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 selected from 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 1.1 5mm, about 0.2mm to about 1.1mm, about 0.2mm to about 1.0mm, about 0.3mm to about 1.25mm, about 0.3mm to about 1.20mm, about 0.3mm to about 1.15mm, about 0.3mm to about 1.1mm, about 0.3mm to about 1.0mm, about 0.4mm to about 1.25mm, about 0.4mm to about 1.20mm, about 0.4mm to about 1.15mm, about 0.4mm to about 1.1mm, about 0.4mm to about 1.0mm, about 0.4mm to about 0.95mm, about 0.4mm to about 0.9mm, and including all subranges and combinations thereof.

[0099] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, the hydraulic diameter unit spacing (CP) of at least one vent-side PPAV described herein is Dh ) is independently selected from, for example, less than or equal to 1.50 mm, less than or equal to 1.40 mm, or less than or equal to 1.30 mm; or from about 0.5 mm to about 1.5 mm, or from about 0.5 mm to about 1.4 mm, or from about 0.5 mm to about 1.3 mm, or from about 0.5 mm to about 1.2 mm, or from about 0.6 mm to about 1.5 mm, or from about 0.6 mm to about 1.4 mm, or from about 0.6 mm to about 1.3 mm, or from about 0.6 mm to about 1.2 mm, or from about 0.7 mm to about 1.5 mm, or from about 0.7 mm to about 1.4 mm, or from about 0.7 mm to about 1.3 mm, or from about 0.7 mm to about 1.2 mm, or from about 0.75 mm to about 1.5 mm, or from about 0.75 mm to about 1.4 mm, or from about 0.75 mm to about 1.3 mm, or from about 0.75 mm to about 1.2 mm, and including all subranges and combinations thereof.

[0100] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV further comprises at least one of: (I) a plurality of channel widths (t c,avg); (ii) multiple width cell pitches (CP) less than about 1.5 mm tc ); (iii) a cell density of about 285 cpsi 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 less than about 50 g / L at 25°C under 5% to 50% n-butane; or (vii) a combination thereof. Features (i)-(vii) are contemplated herein in conjunction with the above-described t c,Dh and / or CP Dh in all combinations of any options.

[0101] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the plurality of channel widths (t c,avg ), such as 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 m; 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, and including all subranges and combinations thereof.

[0102] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the plurality of width cell spacings (CP) of the PPAV tc) (the average of multiple channel widths of channels having approximately the same cross-sectional dimensions and excluding the peripheral channel (i.e., peripheral unit) in the cross-section plus the average channel wall thickness (excluding the outer surface layer wall thickness))) such as less than 1.6 mm, less than 1.55 mm, 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 ... From about 1.5 mm, or from about 0.6 mm to about 1.4 mm, or from about 0.6 mm to about 1.3 mm, or from about 0.6 mm to about 1.2 mm, or from about 0.7 mm to about 1.5 mm, or from about 0.7 mm to about 1.4 mm, or from about 0.7 mm to about 1.3 mm, or from about 0.7 mm to about 1.2 mm, or from about 0.75 mm to about 1.5 mm, or from about 0.75 mm to about 1.4 mm, or from about 0.75 mm to about 1.3 mm, from about 0.75 mm to about 1.25 mm, or from about 0.75 mm to about 1.2 mm, and including all subranges and combinations thereof.

[0103] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the cell density of the PPAV (i.e., channels or cells per square inch if viewed in cross-section ("cpsi")) is, for example, from about 285 cpsi to about 1000 cpsi, from about 300 cpsi to about 1000 cpsi, from about 325 cpsi to about 1000 cpsi, from about 350 cpsi to about 1000 cpsi, from about 375 cpsi to about 1000 cpsi, from about 400 cpsi to about 1000 cpsi, from about 425 cpsi to about 1000 cpsi, , about 450 cpsi to about 1000 cpsi, about 500 cpsi to about 1000 cpsi, about 550 cpsi to about 1000 cpsi, about 600 cpsi to about 1000 cpsi; or 300 cpsi to about 950 cpsi, 300 cpsi to about 900 cpsi, 300 cpsi to about 850 cpsi, 300 cpsi to about 800 cpsi; or about 400 cpsi to about 900 cpsi, 400 cpsi to about 850 cpsi, 400 cpsi to about 800 cpsi, and including all sub-ranges and combinations thereof.

[0104] In any aspect or embodiment 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, 0.1 mm to about 0.5 mm, about 0.1 mm to about 0.45 mm; or about 0.15 mm to about 0.5 mm, 0.15 mm to about 0.4 mm; or about 0.2 mm to about 0.5 mm; or about 0.2 mm to about 0.45 mm, and including all subranges and combinations thereof. The average channel wall thickness is determined as described herein.

[0105] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV has a BWC (g / dL) of, 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 less than about 0.5 g / dL; or from about 0.5 g / dL to about 10 g / dL, from about 0.5 g / dL to about 9 g / dL, from about 0.05 g / dL to about 1.0 g / dL, or from about 0.09 g / dL to about 1.5 g / dL. .5 g / dL to about 8 g / dL, about 0.5 g / dL to about 7 g / dL, about 0.5 g / dL to about 6 g / dL, about 0.5 g / dL to about 5 g / dL, about 0.5 g / dL to about 4 g / dL, about 0.5 g / dL to about 3 g / dL, about 0.5 g / dL to about 2 g / dL, about 0.5 g / dL to about 1 g / dL; or about 1 g / dL to about 10 g / dL, about 1 g / dL to about 9 g / dL, about 1 g / dL to about 8 g / dL, about 1 g / dL to about 7 g / dL, about 1 g / dL to about 6 g / dL, about 1 g / dL to about 5 g / dL, about 1 g / dL to about 4 g / dL, about 1 g / dL to about 3 g / dL, about 0.5 g / dL to about 2 g / dL, about 0.5 g / dL to about 1 g / dL; / dL to about 2 g / dL; or from 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 g / dL to about 6.0 g / dL, about 2.0 g / dL to about 5.5 g / dL, about 2.0 g / dL to about 5.0 g / dL, about 2.0 g / dL to about 4.5 g / dL; or from 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 g / dL, about 3.0 to about 4.5 g / dL, 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 g / dL to about 6.0 g / dL, about 3.0 g / dL to about 5.5 g / dL, about 2.5 g / dL to about 5.0 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 g / dL to about 6.0 g / dL, about 3.0 g / dL to about 5.5 g / dL, about 3.0 g / dL to about 5.0 g / dL, or about 3.0 to about 4.5 g / dL, including all subranges and combinations thereof.

[0106] Unless otherwise stated, BWC is measured according to the methods described herein.In any aspect or embodiment described herein, the length of the PPAV described herein (ie, each article or component) is between about 25 mm and 250 mm, or between about 50 mm and 150 mm.

[0107] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the incremental adsorption capacity (IAC) between 5% and 50% n-butane at 25°C of the PPAV is, 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 g / L to about 50 g / L, from about 5 g / L to about 45 g / L, from about 5 g / L to about 40 g / L, from about 5 g / L to about 35 g / L, from about 5 g / L to about 30 g / L, from about 5 g / L to about 50 g / L, from about 5 g / L to about 50 g / L, from about 5 g / L to about 45 g / L, from about 5 g / L to about 40 g / L, from about 5 g / L to about 35 g / L, from about 5 g / L to about 30 g / L, from about 5 g / L to about g / L to about 25 g / L, about 5 g / L to about 20 g / L, about 5 g / L to about 15 g / L, about 5 g / L to about 10 g / L; or from about 10 g / L to about 50 g / L, from about 10 g / L to about 45 g / L, from about 10 g / L to about 40 g / L, from about 10 g / L to about 35 g / L, from about 10 g / L to about 30 g / L, from about 10 g / L to about 25 g / L, from about 10 g / L to about 20 g / L; or from about 15 g / L to about 50 g / L, from about 15 g / L to about 45 g / L, from about 15 g / L to about 40 g / L, from about 15 g / L to about 35 g / L, from about 15 g / L to about 30 g / L, from about 15 g / L to about 25 g / L, or from about 15 g / L to about 20 g / L, and including all subranges and combinations thereof.

[0108] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, no more than (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 of purge or no more than (i.e., less than or equal to) 150, 140, 130, 120, 110, 100, 90, 80, 75, 70, 65, 60 10,15,16,17,18,19,20,21,22,23,24,25,27,28,29,20,21,20,19,18,17,16,15,14,13,12,11,10,9,8,7,6,5,4,3,2,10,15,16,17,18,19,20,21,22,23,24,25,27,28,29,20,21,22,23,24,25,27,28,27,28,27,28,27,28,27,28,27,28,27,28,27,28,27,28,27,28,27,27,28,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,27,

[0109] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV

[0110] Including channels with a width of less than 1.25 mm and a cell pitch of less than 1.5 mm. In certain embodiments, the PPAV exhibits low vapor release characteristics as measured by an incremental adsorption capacity (between 5% and 50% n-butane) of less than 50 g / L at n-butane vapor concentrations between 5% and 50% by volume at 25°C.

[0111] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV

[0112] Having features as exemplified by the experimental results provided herein, including, for example, numerical ranges based on the data in the experimental results.

[0113] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV is in the form of a prism, such as round (i.e., cylindrical), square, rectangular, triangular, pentagonal, etc., and thus the parallel channels extend inwardly parallel to each other and to the outer surface along the length of the prism.

[0114] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV comprises an adsorbent material derived from at least one of wood, wood chips, 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 aspect or embodiment described herein, the PPAV comprises an adsorbent material derived from wood or wood chips.

[0115] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV comprises an adsorbent, such as activated carbon or charcoal.

[0116] In any aspect or embodiment 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, charcoal, zeolites, clays, porous polymers, porous alumina, porous silica, molecular sieves, kaolin, titania, cerium oxide, metal organic frameworks, and combinations thereof.

[0117] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV comprises one or more binders, for example, an organic binder such as carboxymethyl cellulose (CMC) or an inorganic binder such as bentonite clay or a combination of binders. In any aspect or embodiment described herein, the PPAV comprises one or more cellulosic binders such as carboxymethyl cellulose (CMC) and one or more inorganic binders such as clay. In certain embodiments, the binder comprises at least one of a clay or a silicate material. For example, in certain 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 Terramin clay, an activated clay, a Fuller's earth clay, an Ormalite clay, a Vitalite clay, a Rectorite clay, a Cordierite, a Ball clay, a Kaolin, or a combination thereof.

[0118] Additional potential adhesives include thermosetting adhesives and hot melt adhesives. Thermosetting adhesives are compositions based on thermosetting resins, which are liquid or solid at ambient temperature and are especially urea-formaldehyde, melamine-urea-formaldehyde or phenol-formaldehyde types, preferably melamine-urea-formaldehyde type resins and emulsions of thermosetting (to) polymers in latex foam. Crosslinking agents can be incorporated into the mixture. As an example of a crosslinking agent, ammonium chloride can be mentioned. Hot melt adhesives are solid at ambient temperature generally and are based on hot melt type resins. Asphalt, tar or any other known adhesive can also be used as an adhesive.

[0119] In any of the embodiments described herein, the binder may 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.

[0120] In any of the embodiments described herein, the binder may include a non-aqueous binder such as clay, phenolic resin, lignin, lignosulfonate, polyacrylate, polyvinyl acetate, polyvinylidene chloride (PVDC), ultra-high molecular weight polyethylene (UHMWPE), etc., fluoropolymers (e.g., 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 difluoride)), 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.

[0121] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV is made from ground activated carbon precursor material cross-linked with a binder, wherein the ground activated carbon material is in powder form. For example, in certain embodiments, a formed PPAV as described herein is prepared by obtaining a powdered activated carbon material and applying the cross-linking binder technology of US6,472,343.

[0122] 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, Pascalit clay, Redmond clay, Terramin clay, activated clay, Fuller's earth clay, Ormalite clay, Vitalite clay, Rectorite clay, cordierite, ball clay, kaolin, or a combination thereof.

[0123] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV is formed into a monolithic structure, such as a honeycomb configuration. In any aspect or embodiment described herein, the PPAV monolithic structure is prepared by a method comprising extruding a blend comprising an adsorbent material and a binder to form a parallel channel shape. In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV (e.g., a PPAV monolithic structure) is prepared by a method comprising coating the channels of a parallel channel structure support with a coating comprising an adsorbent material. In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV monolithic structure is prepared by a method comprising coating the channels of a parallel channel structure support with a coating comprising a carbonaceous material, which is converted in situ into an adsorbent by further thermal treatment and / or chemical treatment (e.g., pyrolysis or chemical activation).

[0124] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV monolithic structure is prepared by a method comprising forming a parallel channel shape by stacking or winding corrugated sheets. In any aspect or embodiment described herein, the parallel channel shape is made of a corrugated sheet comprising an adsorbent. In certain embodiments, the parallel channel shape is made of a corrugated sheet in which an adsorbent is present in a coating. In any aspect or embodiment described herein, the PPAV or at least one vent side PPAV of the evaporative emission control system described herein, the monolithic structure is prepared by a method comprising co-rolling a solid adsorbent sheet or layer with another sheet or another material to produce parallel channels. In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV monolithic structure is prepared by a method comprising rolling a solid adsorbent sheet or layer comprising ribs or nuggets to produce parallel channels. In any aspect or embodiment described herein, the adsorbent material is formed into a structure comprising a combination of any of the foregoing structures.

[0125] 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 of about 2 grams of n-butane per liter (g / L) to about 35 grams of n-butane per liter at a vapor concentration of n-butane between 5 vol% and 50 vol% at 25° C. 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 of about 2 grams of n-butane per liter (g / L) to about 30 grams of n-butane per liter at a vapor concentration of n-butane between 5 vol% and 50 vol% at 25° C. 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 of about 2 grams of n-butane per liter (g / L) to about 25 grams of n-butane per liter at a vapor concentration of n-butane between 5 vol% and 50 vol% at 25° C. 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 of about 2 grams of n-butane per liter (g / L) to about 20 grams of n-butane per liter at a vapor concentration of n-butane between 5 vol% and 50 vol% at 25° C.

[0126] 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 of about 2 grams of n-butane per liter (g / L) to about 15 grams of n-butane per liter at a vapor concentration of n-butane between 5 vol% and 50 vol% at 25°C. 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 of about 2 grams of n-butane per liter (g / L) to about 10 grams of n-butane per liter at a vapor concentration of n-butane between 5 vol% and 50 vol% at 25°C.

[0127] 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 of about 2 grams of n-butane per liter (g / L) to about 5 grams of n-butane per liter at a vapor concentration of n-butane between 5 vol% and 50 vol% at 25° C. 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 of about 5 grams of n-butane per liter (g / L) to about 30 grams of n-butane per liter at a vapor concentration of n-butane between 5 vol% and 50 vol% at 25° C.

[0128] 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 of about 10 grams of n-butane per liter (g / L) to about 30 grams of n-butane per liter at a vapor concentration of n-butane between 5 vol% and 50 vol% at 25° C. 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 of about 15 grams of n-butane per liter (g / L) to about 25 grams of n-butane per liter at a vapor concentration of n-butane between 5 vol% and 50 vol% at 25° C.

[0129] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the PPAV has a gram-total ("g-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 certain embodiments, the g-tot of the PPAV is less than 10 g. BWC is 0.1g-20g, 0.1g-20g, 0.1g-19.5g, 0.1g-18g, 0.1g-17.5g, 0.1g-17g, 0.1g-16.5g, 0.1g -16g, or 0.1g-15.5g, 0.1g-15g, 0.1g-14.5g, 0.1g-14g, 0.1g-13.5g, 0.1g-13g, 0.1g-12.5g, g-tot BWC of 0.1 g-12 g, 0.1 g-11.5 g, or 0.1 g-11 g, 0.1 g-10.5 g, 0.1 g-10 g, 0.1 g-9.5 g, 0.1 g-9 g, 0.1 g-8.5 g, 0.1 g-8 g, 0.1 g-7.5 g, 0.1 g-7 g, or 0.1 g-6.5 g, 0.1 g-6 g, 0.1 g-5.5 g, or 0.1 g-5 g, or one or more examples. As used herein, "gram-total BWC" refers to the grams of butane purged from the PPAV.

[0130] In any aspect or embodiment 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.

[0131] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the length / hydraulic diameter ratio of the PPAV described herein is between about 0.3 and 12.5, or between about 1.2 and 5.2.

[0132] In any aspect or embodiment 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 cells in cross section), or about 680 to 1365 channels (or cells in cross section), including partial cells (e.g., cells in the cross-sectional perimeter of a cylindrical portion). It will be apparent to one skilled in the art that the cells of the PPAV represent a cross-sectional view of the channels extending along the interior length of the PPAV. Therefore, the number and density of the cells are equivalent to the number and density of the channels.

[0133] In any aspect or embodiment of the PPAV, evaporative emission control system, or evaporative emission control canister system described herein, the total channel area of ​​the PPAV described herein is about 60 mm 2 and 2760mm 2 Between, or about 125mm 2 and 660mm 2 between.

[0134] In any aspect or embodiment 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 kPa to 2.7 kPa or about 0.03 kPa to 0.9 kPa at 40 lpm.

[0135]

[0013] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, the canister system described herein has a total sorbent particle volume of between 1 liter and 5 liters.

[0136] In any aspect or embodiment 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, charcoal, zeolites, clays, porous polymers, porous alumina, porous silica, molecular sieves, kaolin, titania, cerium oxide, metal organic frameworks, and combinations thereof.

[0137] The adsorbent material may include any one or more of the above features, which may be combined in various ways according to the present description and are expressly contemplated herein.

[0138] In additional aspects, the present description provides an evaporative emission control system including one or more canisters including at least one PPAV as described herein.

[0139] Figure 1An exemplary embodiment of an evaporative emission control canister system 100 is described, which has a series of adsorbent volumes in a single canister. The canister system 100 includes a screen or foam 102, a dividing wall 103, a fuel vapor inlet 104 from the fuel tank, a vent 105 to the atmosphere, a purge outlet 106 to the engine, a fuel side or initial adsorbent volume 201, and a vent side or subsequent adsorbent volume 202. The screen or foam 102 provides accommodation and loading of the adsorbent volume and acts as a distributor to evenly distribute the vapor flow to the adsorption volume. The two chambers containing the adsorbent volumes 201 and 202 are separated by a dividing wall 103 and connected by a channel 107 for sequential vapor flow under the load screen 102. Therefore, in this example, 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 ventilation side adsorbent 202 to the vent 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 then into the vent side or subsequent adsorbent volume 202 before being released into the atmosphere through the vent 105 of the canister system. Once the engine is started, ambient air is drawn into the canister system 100 through the vent 105. Purge air flows through the volume 202 in the canister and ultimately through the fuel side or initial adsorbent volume 201. This purge flow desorbs the fuel vapor adsorbed on the adsorbent volume 202 through 201 before entering the internal combustion engine through the purge outlet 106. Those skilled in the art will appreciate that Figures 2 to 8 Additional exemplary canister systems are shown that define an adsorbent volume in fluid communication along a similar fuel vapor / air flow path.

[0140] 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. Figure 2 , the fuel side or initial adsorbent volume 201 may have additional or multiple vent side (or subsequent) adsorbent volumes 202 prior to the loading screen 102 above the plenum 107, such as Figure 2 Other vent-side (or subsequent) adsorbent volumes 203 and 204 may be found on the other side of the dividing wall.

[0141] Furthermore, in other embodiments, the canister system may include more than one type of vent side adsorbent volume, which may be independently selected and / or contained in one or more containers. Figure 3As shown in FIG. 1 , an auxiliary chamber 300 containing a vent-side adsorbent volume 301 (such as the PPAV described herein) can be connected in series with a main tank 101 containing multiple adsorbent volumes in terms of air and vapor flow, connected by a connecting pipe or vent pipe 108 for vapor flow. Figure 4 As shown, auxiliary chamber 300 may include two vent side adsorbent volumes 301 and 302 in series, including, for example, at least one PPAV as described herein. Adsorbent volumes 301 and 302 may also be included in a series chamber or auxiliary tank instead of Figure 4 In a single room 300.

[0142] Figures 5 to 8 Additional exemplary tank systems contemplated by the present invention are shown. Figure 5 and Figure 6 A system is shown including a main canister 101 including an initial (fuel side) adsorbent volume 501 and subsequent (vent side) adsorbent volumes 202, 203, and 204. The system includes a connection tube or vent tube 108 on the vent side leading to a make-up canister 300 including an additional vent side adsorbent volume 502 prior to the vent 105, such as the PPAV described herein. Figure 7 A system is shown having an initial (fuel side) adsorbent volume 501 and a subsequent adsorbent volume 202 in a main tank 101 connected via a connecting tube 108 to a make-up tank 300 and 503 including subsequent (vent side) adsorbent volumes 502, 504 prior to a vent 105. In an exemplary embodiment, at least one of 502 or 504 is a PPAV as described herein. Figure 8 An example of a single canister 101 design is shown that includes an initial (fuel side) adsorbent volume 501, a plenum space 107 leading to subsequent (vent side) adsorbent volumes 203 and 204, a second plenum space 109 leading to additional subsequent (vent side) adsorbent volumes 502 and 504 prior to vent 105. In an exemplary embodiment, at least one of 502 or 504 is a PPAV as described herein.

[0143] As used herein, the term "upstream" refers to a position / volume in a system flow path that comes into contact with a fluid (e.g., fuel vapor) before or prior to another position / volume in the system along the system flow path in the same relative direction. The term "downstream" refers to a position / volume in a system flow path that comes into contact with a fluid (e.g., fuel vapor) after or subsequent to 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 positioned closer to a fuel vapor inlet relative to another position / volume.

[0144] The term "fuel-side adsorbent volume" is used to refer to the volume of adsorbent material near the fuel vapor source and, therefore, located earlier in the fuel vapor flow path than a subsequent adsorbent volume (herein, a "vent-side adsorbent volume") that must be located closer to the vent. As will be appreciated by those skilled in the art, the vent-side or subsequent adsorbent volume is contacted earlier in the purge air flow path during the purge cycle. For convenience, the fuel-side adsorbent may be referred to as the "initial adsorbent volume" because it is located upstream in the fuel vapor flow path relative to the vent-side or subsequent adsorbent volumes, but the initial adsorbent volume is not necessarily the first adsorbent volume in the canister.

[0145] In any aspects or embodiments of the evaporative emission control systems or evaporative emission control canister systems described herein, the canister may further include additional adsorbent volumes as described herein, for example, at least one adsorbent volume in the chamber closest to the fuel tank (i.e., a fuel-side adsorbent volume), and / or at least one adsorbent volume in the chamber closer to the outlet to the atmosphere (i.e., a subsequent or vent-side adsorbent volume), including a PPAV as described herein.

[0146] In additional embodiments, the present invention provides an evaporative emission control canister system comprising one or more canisters having a plurality of chambers, each chamber defining a volume, the plurality of chambers being connected or fluidly connected to allow a fluid (e.g., air, gas, or fuel vapor) to flow directional and sequentially from one chamber to the next, wherein at least one chamber comprises a PPAV as described herein. In certain embodiments, the canister system comprises at least one additional adsorbent volume. In certain embodiments, the adsorbent volume is located within a single canister or within a plurality of canisters that are connected to allow sequential contact by fuel vapor.

[0147] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, the PPAV described herein is incorporated into a vent side volume of a 2.1 liter test can having dimensions described herein and exhibits a two-day DBL percolation emissions performance (second day diurnal ventilation 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.

[0148] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, about 10 mg to about 100 mg, about 10 mg to about 90 mg, about 10 mg to about 80 mg, about 10 mg to about 70 mg, about 10 mg to about 60 mg, about 10 mg to about 50 mg, about 10 mg to about 40 mg, about 10 mg to about 30 mg, about 10 mg to about 20 mg, about 15 mg to about 100 mg, about 15 mg to about 90 mg, about 15 ... 0 mg, about 15 mg to about 70 mg, about 15 mg to about 60 mg, about 15 mg to about 50 mg, about 15 mg to about 40 mg, about 15 mg to about 30 mg, about 15 mg to about 20 mg, about 20 mg to about 100 mg, about 20 mg to about 90 mg, about 20 mg to about 80 mg, about 20 mg to about 70 mg, about 20 mg to about 60 mg, about 20 mg to about 50 mg, about 20 mg to about 40 mg, about 20 mg to about 30 mg, about 30 mg to about 1 00mg, 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 to about 90mg, about 40mg to about 80mg, about 40mg to about 70mg, about 40mg to about 60mg, about 40mg to about 50mg, about 50mg to about 100mg, about 50mg to about 90mg, about 50mg to about Two-day DBL percolation discharge performance of about 80 mg, about 50 mg to 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, included values ​​and ranges.

[0149] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein that includes a PPAV as described herein, the above two-day DBL permeation emissions performance is provided at no more than 210 liters (i.e., 100 BV) or no more than 315 liters (i.e., 150 BV) of purge applied after the 40 g / hr butane loading step as measured by the 2012 BETP.

[0150] In any aspects or embodiments of the evaporative emission control systems or evaporative emission control canister systems described herein, the evaporative emission control canister system includes at least one fuel side adsorbent volume and at least one subsequent (i.e., vent side) adsorbent volume, wherein at least one of the at least one fuel side adsorbent volume or the at least one subsequent adsorbent volume includes a PPAV as described herein.

[0151]

[0013] In any aspect or embodiment 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 a device for adding heat by electrical resistance or heat conduction.

[0152] In any aspect or embodiment 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 adsorbent volumes having a substantially uniform cell structure at or near a terminal end of a fuel vapor flow path.

[0153] In certain embodiments, at least one or more fuel side or initial adsorbent volumes and at least one or more vent side or subsequent adsorbent volumes are in vapor or gas communication and define an air and vapor flow path therethrough. The air and vapor flow path allows or promotes directional air or vapor flow or diffusion between the individual adsorbent volumes in the canister system. For example, the air and vapor flow path promotes the flow or diffusion of fuel vapor from at least one or more fuel side or initial adsorbent volumes to at least one or more vent side or subsequent adsorbent volumes, including the PPAV described herein.

[0154] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, at least one fuel side or initial adsorbent volume and at least one vent side or subsequent adsorbent volume may be located in a single canister, separate canisters, or a combination of both. For example, in certain embodiments, the system includes one or more canisters, the one or more canisters including a fuel side or initial adsorbent volume and one or more vent side or subsequent adsorbent volumes, wherein the vent side or subsequent adsorbent volume is connected to the fuel side initial adsorbent volume so that its vapor or gas is connected, thereby forming a vapor flow path, and allowing air and / or vapor to flow or diffuse therethrough, and wherein at least one vent side adsorbent volume is a vent side PPAV as described herein. In certain aspects, the canister allows sequential contact of the adsorbent volumes with air or fuel vapor.

[0155] In additional embodiments, an evaporative emission control canister system includes a canister including an initial adsorbent volume and one or more subsequent adsorbent volumes connected to one or more separate canisters including at least one additional subsequent adsorbent volume (including the vent-side PPAV described herein), wherein the subsequent adsorbent volume is connected to the initial adsorbent volume so that it is vapor or gaseous communication, thereby forming a vapor flow path and allowing air and / or fuel vapor to flow or diffuse therethrough.

[0156] In any aspect or embodiment of an evaporative emission control system or evaporative emission control canister system described herein, the evaporative emission control canister system comprises one or more canisters comprising a fuel side or initial adsorbent volume and one or more vent side PPAVs, the one or more vent side PPAVs comprising an exterior surface and a plurality of parallel channels or channels extending therethrough parallel to the exterior surface, and wherein the parallel channels or channels are configured to have an average channel hydraulic diameter (t less than or equal to 1.25 mm). c,Dh ), hydraulic diameter unit spacing (CP) less than or equal to 1.5 mm Dh ) or a combination thereof, and at least one of the following: (i) a plurality of channel widths (t c,avg ); (ii) multiple channel width cell pitches (CP) less than about 1.5 mm tc,avg ); (iii) a cell density of about 285 cpsi 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 less than about 50 g / L at between 5% and 50% n-butane at 25° C.; or (vii) a combination thereof, wherein the fuel side adsorbent volume and the PPAV are in vapor or gas communication to form a vapor flow path that allows air and / or fuel vapor to flow or diffuse therethrough.

[0157] In certain embodiments, the evaporative emission control canister system has a two-day diurnal ventilation loss (DBL) of no more than 50, 40, 30, 20, or 10 mg at no more than 315, 300, 290, 280, 270, 260, 250, 240, 230, 220, 210, 200, 190, 180, 170, 160, 150, 140, 130, 120, 110, or 100 liters of purge or no more than 150, 140, 130, 120, 110, 100, 90, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, or 30 bed volumes (BV) applied after the 40 g / hr butane loading step as determined by the 2012 California Bleed Emissions Test Procedure (BETP).

[0158] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, the evaporative emission control canister system includes a canister including a fuel side or initial adsorbent volume and a PPAV, wherein the PPAV is a monolithic piece such as a honeycomb having an average channel hydraulic diameter of less than 1.25 mm and a hydraulic diameter cell spacing of less than 1.5 mm. In certain embodiments, the plurality of channels having substantially the same cross-sectional dimensions and excluding the peripheral channels in the cross-section have a plurality of channel widths of less than 1.25 mm and a plurality of width cell spacings of less than 1.5 mm.

[0159] In any aspects or embodiments of the evaporative emission control systems or evaporative emission control canister systems described herein, the fuel side or initial adsorbent volume is the first and / or second adsorbent volume and, therefore, the vent side or subsequent adsorbent volume (including the PPAV described herein) is downstream in the fluid flow path toward the vent, whether in the same canister or a separate canister or both.

[0160] In any aspect or embodiment of the evaporative emission control system or evaporative emission control canister system described herein, the present invention provides an evaporative emission control canister system, which includes one or more canisters, the one or more canisters having a plurality of chambers, each chamber defining a volume, the plurality of chambers being fluidly connected to allow fluid or vapor to flow directly from one chamber to the next chamber, and at least one chamber comprising at least one parallel path adsorbent volume (PPAV), wherein the at least one PPAV has an incremental adsorption capacity (IAC) of less than 35 g / L at a vapor concentration between 5 vol% n-butane and 50 vol% n-butane at 25°C, an average channel hydraulic diameter of less than 1.25 mm, and a hydraulic diameter cell spacing (which is the sum of the average cell channel hydraulic diameter plus the average cell wall thickness (excluding the outer skin wall thickness)) of less than 1.5 mm.

[0161] In any aspect or embodiment of an evaporative emission control system or evaporative emission control canister system described herein, the present invention provides an evaporative emission control canister system comprising one or more canisters, the one or more canisters comprising: at least one fuel-side adsorbent volume; and at least one vent-side parallel channel adsorbent volume (PPAV), wherein the at least one PPAV has an incremental adsorption capacity (IAC) of less than 35 g / L at a vapor concentration between 5 vol% n-butane and 50 vol% n-butane at 25°C, an average channel hydraulic diameter of less than 1.25 mm, and a hydraulic diameter unit spacing of less than 1.5 mm.

[0162] In any aspect or embodiment of an evaporative emission control system or evaporative emission control canister system described herein, the present invention provides an evaporative emission control canister system comprising one or more canisters, the one or more canisters comprising: at least one fuel-side adsorbent volume; and at least one vent-side parallel channel adsorbent volume (PPAV), wherein the at least one PPAV has an incremental adsorption capacity (IAC) of less than 35 g / L at a vapor concentration between 5 vol% n-butane and 50 vol% n-butane at 25°C, an average channel hydraulic diameter (t c,Dh ) and a hydraulic diameter unit spacing (CP) less than 1.5 mm Dh ).

[0163] In any aspect or embodiment of an evaporative emission control system or evaporative emission control canister system described herein, the present invention provides an evaporative emission control canister system comprising one or more canisters having a plurality of chambers, each chamber defining a volume, the plurality of chambers being fluidly connected to allow fluid or vapor to flow directly from one chamber to the next chamber, and at least one chamber comprising at least one parallel path adsorbent volume (PPAV) as described herein, wherein the at least one 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 a vapor concentration between 5 vol% n-butane and 50 vol% n-butane at 25°C, a plurality of channel widths (t c,avg ), and multiple width cell pitches (CP) less than 1.5 mm tc,avg ) (which is the average of multiple channel widths of channels having approximately the same cross-sectional dimensions and excluding peripheral channels or cells in the cross-section plus the average channel wall thickness (excluding the outer surface layer wall thickness)).

[0164] In any aspect or embodiment of an evaporative emission control system or evaporative emission control canister system described herein, the present invention provides an evaporative emission control canister system comprising one or more canisters, the one or more canisters comprising: at least one fuel side adsorbent volume; and at least one vent side parallel channel adsorbent volume (PPAV), wherein the at least one vent side PPAV has an incremental adsorption capacity (IAC) of less than 35 g / L at a vapor concentration between 5 vol% n-butane and 50 vol% n-butane at 25°C, a plurality of channel widths (t c,avg ) and multiple width cell pitches (CP) less than 1.5 mm tc,avg ).

[0165] In any aspect or embodiment of an evaporative emission control system or evaporative emission control canister system described herein, the present invention provides an evaporative emission control canister system comprising one or more canisters, the one or more canisters comprising: at least one fuel side adsorbent volume; and at least one vent side parallel channel adsorbent volume (PPAV), wherein the at least one vent side PPAV has an incremental adsorption capacity (IAC) of less than 25 g / L at a vapor concentration between 5 vol% n-butane and 50 vol% n-butane at 25°C, a plurality of channel widths (t c,avg ) and multiple width cell pitches (CP) less than 1.5 mm tc,avg ).

[0166] In another aspect, the present invention provides an evaporative emission control system, the evaporative emission control system comprising: a fuel tank for storing fuel; an engine having an air induction system and adapted to consume the fuel; an evaporative emission control canister system comprising one or more canisters, the one or more canisters comprising a plurality of adsorbent volumes, the plurality of adsorbent volumes comprising: at least one fuel side adsorbent volume; and at least one vent side parallel channel 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 a vapor concentration between 5 vol% n-butane and 50 vol% n-butane at 25°C, an average channel hydraulic diameter (t c,Dh ) and a hydraulic diameter unit spacing (CP) less than 1.5 mm Dh ); a fuel vapor inlet conduit connecting the evaporative emission control canister system to the fuel tank; a fuel vapor purge conduit connecting the evaporative emission control canister system to an air induction system of the engine; and a vent for venting the evaporative emission control canister system and allowing purge air to enter 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 adsorbents to the vent, and an air flow path from the vent through the plurality of adsorbent volumes and a fuel vapor purge outlet.

[0167] In another aspect, the present invention 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 channel adsorbent volume (PPAV), and contacting fuel vapor with the adsorbent volume, wherein the at least one vent-side PPAV has an average channel hydraulic diameter of less than 1.25 mm and a hydraulic diameter cell spacing of less than 1.5 mm, and optionally an incremental adsorption capacity (IAC) of less than 50 g / L at a vapor concentration between 5 vol % n-butane and 50 vol % n-butane at 25°C.

[0168] In another aspect, the present invention provides a method for reducing fuel vapor emissions in an evaporative emission control system, the method comprising providing one or more canisters, the one or more canisters comprising a plurality of adsorbent volumes, the plurality of adsorbent volumes comprising: at least one fuel side adsorbent volume; and at least one vent side parallel channel adsorbent volume (PPAV), wherein 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 width unit spacings of less than 1.5 mm, and optionally an incremental adsorption capacity (IAC) of less than 50 g / L at a vapor concentration between 5 vol % n-butane and 50 vol % n-butane at 25°C.

[0169] In any aspect or embodiment described herein, the at least one parallel-channel adsorbent volume or at least one vent-side parallel-channel adsorbent volume has at least one of the following: an incremental adsorption capacity (IAC) of less than 50 g / L at a vapor concentration between 5 vol% n-butane and 50 vol% n-butane at 25°C, an average channel hydraulic diameter of less than 1.25 mm, and a hydraulic diameter unit spacing of less than 1.5 mm, or a combination thereof. In any aspect or embodiment described herein, the at least one parallel-channel adsorbent volume or at least one vent-side parallel-channel adsorbent volume has at least one of the following: an incremental adsorption capacity (IAC) of less than 50 g / L at a vapor concentration between 5 vol% n-butane and 50 vol% n-butane at 25°C, multiple channel widths of less than 1.25 mm, and multiple width unit spacings of less than 1.5 mm, or a combination thereof.

[0170] In any aspect or embodiment described herein, the evaporative emission control canister system includes at least one fuel side adsorbent volume, at least one vent side PPAV, and optionally at least one additional vent side adsorbent volume.

[0171] In any aspect or embodiment described herein, the adsorbent volume is located within a single canister or within multiple canisters that are connected to allow sequential contact by fuel vapor.

[0172] In any aspect or embodiment described herein, the at least one vent-side PPAV is an activated carbon honeycomb.

[0173] In any aspect or embodiment described herein, the at least one additional vent-side sorbent volume is an activated carbon honeycomb.

[0174] In any aspect or embodiment described herein, the activated carbon is derived from a material comprising a member selected from the group consisting of wood, wood chips, 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, and combinations thereof.

[0175] In any aspect or embodiment described herein, the form of the adsorbent comprises 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 structured media, wound structured media, folded structured media, pleated structured media, corrugated structured media, cast structured media, bonded structured media, nonwoven fabrics, woven fabrics, sheets, paper, foams, hollow cylinders, stars, twisted spirals, asterisks, configured strips, and combinations thereof.

[0176] In any aspect or embodiment described herein, the tank system further comprises a heating unit.

[0177] In any aspect or embodiment described herein, the evaporative emission control canister system includes at least one vent side parallel channel adsorbent volume (PPAV), wherein the at least one PPAV has an average channel hydraulic diameter of less than 1.25 mm and a hydraulic diameter unit spacing of less than 1.50 mm, wherein the at least one vent side PPAV optionally has an effective BWC of less than about 10 g / dL, an effective incremental adsorption capacity of less than about 50 grams of n-butane / liter (g / L) at a vapor concentration between 5 vol % n-butane and 50 vol % n-butane at 25° C., or a combination thereof.

[0178] Additional aspects and embodiments will be apparent to those skilled in the art based on the above description in view of the following embodiments, which embodiments are expressly considered to be a part of the specification as if explicitly set forth herein.

[0179] Examples

[0180] Determination of apparent density, BWC and activity of powdered butane

[0181] ASTM D2854 may be used to determine the nominal density of particulate adsorbents, such as granular and pelletized adsorbents having a size and shape commonly used for evaporative emission control in fuel systems.

[0182] ASTM D5228 can be used to determine the butane working capacity (BWC) of an adsorbent volume containing granular and / or pelletized adsorbents. Butane retention (in g / dL) is calculated as the difference between the volumetric butane activity (i.e., g / cc apparent density multiplied by g / 100 g butane activity) and the g / dL BWC.

[0183] For powdered activated carbon components for extrusion, the powder butane activity ("pBACT") can be measured by any method known to those skilled in the art that is considered equivalent to determining the value, i.e., the equilibrium capacity weight (grams) of a dried powder sample when exposed to 1.00 atm n-butane partial pressure for a sample treated with a thermostat at 25°C. For example, one suitable alternative to pBACT is based on the ASTM 5228 method, as described in US2019 / 0226426A1, which is incorporated herein by reference in its entirety.

[0184] A modified version of the ASTM D5228 method can be used to determine the butane working capacity (BWC) of a particulate, honeycomb, monolith, and / or sheet adsorbent volume. The modified ASTM D5228 method can also be used for particulate adsorbents, where the particulate adsorbent includes fillers, voids, structural components, or additives. In addition, the ASTM D5228 modified method can be used in cases where the particulate adsorbent is not compatible with the standard method ASTM D5228, for example, a representative adsorbent sample cannot be easily placed as a 16.7 mL fill in a sample tube for testing.

[0185] A modified version of the ASTM D5228 method is as follows. The adsorbent sample (e.g., PPAV honeycomb or monolith) is dried at 110±5C for a minimum of three hours and then placed in a desiccator to cool. The dry mass of the adsorbent sample is recorded. The mass of the empty test assembly (47 mm inner diameter × 200 mm length) is measured before the adsorbent sample is assembled into the test assembly. Next, the test assembly is installed in the flow apparatus and loaded with n-butane gas at a butane flow rate of 500 ml / min at 25C and 1 atmosphere 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 loading step can be repeated for consecutive 5-minute flow intervals until a constant mass is reached. In the examples described herein, the loading time and purge time are calculated based on the component volume. For example, the total butane loading time for a 35 mm diameter 150 mm length honeycomb is 87 minutes to 92 minutes. For situations where the volume can be removed and tested intact, the test assembly may be a holder for a honeycomb or monolithic component. Alternatively, the volume may need to be a section of a canister system, or a suitable reconfiguration of the volume with the contents properly oriented to the gas flow otherwise encountered in the canister system.

[0186] The test assembly is then mounted in the test apparatus and purged with 2 liters / minute of dry air at 25°C and 1 atm for a set selected purge time (± 0.2 minutes) according to the formula:

[0187] Purge time (minutes) = (719 volumes (ml)) / (2000 (ml / min)).

[0188] The direction of the air purge flow in the BWC test is the same as the direction of 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 completion of the test.

[0189] The butane working capacity (BWC) of the adsorbent samples was determined using the following equation:

[0190] BWC (g / dL) = amount of butane purged (g) / nominal adsorbent volume (dL).

[0191] Wherein the amount of butane purged = the mass of the test assembly after loading - the mass of the test assembly after purging. For the example including a cylindrical PPAV, the following calculation is also used:

[0192] - Apparent density (g / mL) was calculated as volume (mL) / mass of adsorbent (g);

[0193] - Adsorbent volume (ml) is calculated as πD o,c (mm)2 L(mm) / 4000;

[0194] - Butane activity (g / 100 g) was calculated as BACT (g / 100 g) = amount of butane loaded (g) / (100 × mass of adsorbent (g));

[0195] -Butane purge rate (%) = BPR (%) is calculated as the amount of butane purged (g) / the amount of butane loaded (g)×100.

[0196] Determination of diurnal ventilation loss (DBL) emissions according to the BETP test

[0197] The evaporative emission control system in the example was tested by a protocol including the following: For testing with a Type A canister system, the defined 2.1 L canister used to generate the DBL emission data had Figure 5 . Three pellet bed volumes 501, 203 and 204 are located in the main tank 101, containing 1.40 L, 0.40 L and 0.30 L of pellets respectively. An exemplary PPAV honeycomb is present in the auxiliary tank 300 as an adsorbent volume 502, including a seal around the cylinder for sealing (not shown in the illustration of the tank) and a thin disk of non-adsorbent open-cell foam ( Figure 5 102 in the above).

[0198] For tests conducted with the Type B canister system (examples are denoted herein by the suffix "B"), the adsorbent bed configuration was the same as for the Type A system except that: 1) a different single grade of carbon pellets was used in the main canister; and 2) Figure 4 The two adsorbent volumes 203 and 204 are constructed as a single 0.70 L volume pellet, such as Figure 6 For the example marked "12a+bB", the tank system is type B except for Figure 7 There are two auxiliary tanks in series. The first auxiliary tank 300 contains a PPAV honeycomb 12a as an adsorbent volume 502, and the second auxiliary tank 503 in series contains a PPAV honeycomb 12b as an adsorbent volume 504, with seals (not shown) and non-adsorbent open-cell foam disks 102 at each end of the two PPAV honeycombs.

[0199] In the A type system, 1.40L BAX 1500( North Charleston, South Carolina, USA) as the adsorbent volume 501, which is located at a height of about 19.5 cm above the load screen 102 located above the plenum 107, and at a height of about 11.1 cm above the load screen 102 located above the plenum 107. The 0.40 L adsorbent volume 203 of the BAX 1500 and the adsorbent volume between the adsorbent volumes 203 and 204 at a height of about 8.4 cm above the loading screen 102 0.3 L adsorbent volume 204 of BAX LBE. The average width of adsorbent volume 501 from dividing wall 103 to the right side wall of the canister is 9.0 cm, and the average width of adsorbent volumes 203 and 204 from dividing wall 103 to its left side wall is about 4.5 cm. Adsorbent volumes 501, 203, and 204 have similar depths (into Figure 5 Each adsorbent bed of pellets was filled with a dry mass determined by apparent density that would meet the respective volume target (fill mass = AD x volume target). Table 1 describes the grade and properties of the main tank adsorbent volume fill. For a Type B tank system, the adsorbent volume in the main tank was filled with only BAX 1100LD, as described in Table 1.

[0200] For tests conducted with Type C tanks, the limiting tank used to generate DBL emission data is Figure 8 This tank system is a commercial tank used in Honda CR-V 2017 vehicles (Evap series HHNXR01221SA / B). Type C tanks are used with instances marked 20a+bC and 21a+bC. Type C systems have a 1.86L BAX1100LD( North Charleston, South Carolina, USA) as an adsorbent volume 501, which is located at a height of about 22.6 cm above the load screen 102 located above the plenum 107, and at a height of about 7.8 cm above the load screen 102 located above the plenum 107. The 0.26L adsorbent volume 203 of BAX 1100LD and the adsorbent volume between 203 and 204 at a height of about 7.4cm above the loading screen 102 0.23L adsorbent volume 204 of BAXLBE. Adsorbent volume 501 is cylindrical and has a diameter of 11.1 cm, and adsorbent volumes 203 and 204 are also cylindrical and have an average diameter of about 6.8 cm. After the air gap 109, there 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.

[0201] Each exemplary canister system was uniformly preconditioned (aged) by repeated cycles of gasoline vapor adsorption based on a main canister (e.g., 630 liters for a 2.1L main canister) using certified Grade 3 fuel (8.7-9.0 RVP, 10% ethanol by volume) and 300 bed volumes of dry air purge at 22.7 LPM. The gasoline vapor loading rate was 40 g / hr and the hydrocarbon composition was 50% by volume, produced by heating two liters of gasoline to about 38°C and bubbling with air at 200 ml / min. Two liters of aliquots of fuel were automatically replaced with fresh gasoline periodically to maintain a roughly constant vapor generation rate until a breakthrough of 5000 ppm, the same as butane, was detected by an FID (flame ionization detector) or infrared detector. A minimum of 25 aging cycles were used on an unused canister. The gasoline working capacity (GWC) was measured as the average weight gain of the loaded vapor loading and the loss of the purge vapor for the last 2-3 cycles and reported as grams per liter of adsorbent volume in the canister system. Proceeding further to measure percolation emission performance, a single butane adsorption / air purge step was performed after the GWC aging cycle. Butane was loaded at 40 g / hour at 50% by volume at one atm to achieve 5000 ppm breakthrough, followed by a one hour soak, followed by a 21 minute purge with dry air, where the total purge volume was achieved by selecting an appropriate constant air purge rate for the time period. The tank system was then soaked at about 25°C with the orifice sealed for about 14-18 hours (where the soak time required was 12-36 hours). Figures 17 to 22 , Figures 25 to 32 and Figure 42 to Figure 44 According to the DBL data in , the total purge volume after the above single butane adsorption loading is 210L, equivalent to, for example, about 91BV-95BV for a full tank system including all adsorbent volumes present (e.g., 2.1L adsorbent volume that satisfies the defined tank) and the vent side activated carbon honeycomb adsorbent 502 placed in the subsequent auxiliary tank 300 or the two activated carbon honeycomb adsorbents 502 and 504 placed in the subsequent series auxiliary tanks 300 and 503. In these configurations, the volume added to the adsorbent pellet volume defined in the main tank is the caliper-measured volume of the size of the activated carbon honeycomb present in the auxiliary tank 300 and (if present) the caliper-measured volume of the size of the second activated carbon honeycomb in the series auxiliary tank 503.

[0202] against Fig.32 and Fig.33 For the DBL data in , for a complete canister system including all adsorbent volumes present, the total purge volume ranges from 210 liters to 310 liters, equivalent to approximately 94 BV to 138 BV. Fig.34 and Fig.35Based on the DBL data in , for a complete canister system including all adsorbent volumes present, the total purge volume ranges from 124 liters to 210 liters, equivalent to approximately 50 BV to 85 BV.

[0203] Next, DBL emissions were generated by connecting the tank port of the example to a fuel tank filled with CARB LEVIII fuel (6.9-7.2 RVP, 10% ethanol). The canister system example where the majority of the pellets present in the main tank were BAX 1500 grade carbon was connected to a 20 gallon tank (total volume) filled with 6.2 gallons of liquid fuel (13.8 gal ullage). The canister system example with BAX 1100LD in the main tank was connected to a 15 gallon tank (total volume) filled with 4.0 gallons of liquid fuel (11 gal ullage). The C-type canister system example was connected to a 14 gallon tank (nominal capacity) filled with 5.6 gallons of liquid fuel.

[0204] Prior to connection, the filled fuel tank was stabilized at 18.3°C for 18-20 hours while venting (where the soak time during ventilation required 12-36 hours). Next, the temperature of the tank and canister system was cycled according to CARB's two-day temperature profile, from 18.3°C to 40.6°C over 11 hours each day, then back to 18.3°C over 13 hours. During the heating phase, emission samples were collected from the example vent into Kynar bags at 6 and 12 hours (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 then drawn into the FID to determine the hydrocarbon concentration. The FID was calibrated with a precisely known butane standard of approximately 5000 ppm concentration. The mass of the emissions (as butane) was calculated from the Kynar bag volume, the emission concentration, and assuming an ideal gas. The mass of the emissions at 6 and 12 hours was added each day. According to CARB's protocol, the day with the highest total emissions is reported as "2-day emissions". In all cases, except for Example 24, the highest emissions were on Day 2. For Example 24, Day 1 emissions were 278 mg, while Day 2 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 C. R. Londonz, and in CARB's LEVIII BETP procedure (California Evaporative Emissions Standards and Test Procedures for 2001 and Later Model Motor Vehicles, Section D.12, March 22, 2012).

[0205] Table 1. Exemplary evaporative emission control canister systems.

[0206]

[0207]

[0208] 1 Figure 6 and Figure 7 The pellet type is 501 in 1.40L volume.

[0209] 2 Figure 6 and Figure 7 The pellet type in a single 0.70L volume 202.

[0210] 3 Figure 7 Example 12a+bB in chamber 300+503

[0211] 4 Examples 20a+bC and 21a+bC as PPAV502+504 in FIG. QX4

[0212] 5 Figure 8 1.86L volume 501 pellet type

[0213] 6 Figure 8 Pellet type in 0.26L volume 203

[0214] 7 Figure 8 Medium 0.23L volume 204 pellet type

[0215] 8 In Table 12, the effects of purging the LEVII systems Examples 1 and 4 are shown. These are measured only at 210 L.

[0216] Test pellet characteristics

[0217] 9 In Table 12, the effects of purging the LEVII systems Examples 1 and 4 are shown. These are at 256 L and 310

[0218] Pellets characteristics tested under L

[0219] Determination of flow restriction

[0220] For honeycomb PPAV monoliths, use a PPAV holder commonly used for tank system testing (e.g. Figures 3 to 5The flow restriction (kPa) was measured in increments of 10 slpm over the range of 10 slpm-100 slpm for the retainer 300 shown in FIG. 1 . A flow restriction correction was applied to the pressure drop over the empty retainer at the same flow rate. The flow restriction data were fit as a function of flow rate using a quadratic equation. The data are reported here as the flow restriction calculated at 40 slpm and at a flow rate equivalent to 46 cm / s superficial velocity by taking into account the cross-sectional area of ​​the monolith as measured by measuring the diameter with a caliper. For a tank system including a main tank and an auxiliary tank containing a PPAV monolith on the vent side, the flow restriction was calculated at 40 slpm and at a flow rate equivalent to 46 cm / s superficial velocity. Figures 3 to 5 Flow restriction ("system load dP") was measured at pressurized load flow from the fuel tank port 104 to the vent port 105 with the engine purge port 106 closed, and flow restriction (system purge dP) was measured at pressurized purge flow from the vent port 105 to the engine port 106 with the fuel tank port 104 closed. A quadratic equation was used to fit the flow restriction data as a function of flow rate, and the system load dP and purge dP are reported here at a calculated 40 slpm.

[0221] Measurement of dynamic butane adsorption capacity

[0222] The PPAV honeycomb monolith samples were placed in a cylindrical sample holder oriented in a vertical direction and tested for dynamic adsorption capacity (DAC) in a chamber at 25° C. according to a load-purge-reload protocol (see US2020 / 0018265A1, which is incorporated herein by reference in its entirety).

[0223] In the DAC test, the sample and its holder are first weighed, and then loaded at 25 ° C, 134mL / min (9.5g / hour butane flow) of 1: 1 n-butane: N2 test gas flow (50 volume % n-butane) until saturation. The flow direction is from the top of the sample holder to the bottom. The gas composition of the effluent flow from the sample holder is monitored by an Emerson X-STREAM IR spectrometer. After the saturation step, the sample and its holder are re-weighed, and then purged with N2 for 10 minutes at 100mL / min in the same flow direction as saturation. After the short purge, the sample and its holder are re-weighed, and then desorbed and adsorbed for 15 minutes with a 10L / min N2 flow in the opposite direction to the initial saturation flow direction relative to the sample (that is, the 10L / min purge gas flow is downward, but the sample is flipped 180°). In a subsequent step, after a final standard 5 minute pause for mechanical conditioning, the gas composition was switched to a mixture of 0.5 vol% butane in N2 at a flow rate of 134 ml / min (0.1 g / hour butane flow), and this loading step was also performed as a downward flow with the same flow direction as the initial saturation relative to the sample (i.e., 0.5 vol% butane flow downward, but the sample was flipped again 180° to its initial orientation). The breakthrough curve of the adsorbate in the effluent stream was recorded using the above-mentioned IR spectrometer.

[0224] The key measured response of the PPAV component in the DAC test is the effluent concentration as the sample experiences progressive saturation over the length of the adsorbent volume, including any background seepage of adsorbate discharge, called breakthrough, and the penetration of a wavefront of adsorbate concentration gradient across the volume, called the mass transfer zone (MTZ). Thus, this adsorption process has three periods: 1) an initial breakthrough period when the adsorbate concentration in the effluent is relatively stable at zero or low as all or nearly all of the inlet adsorbate is removed by the adsorbent bed, 2) a period of accelerated and then decelerated rise in adsorbate concentration in the effluent stream as the MTZ breaks through, and 3) a period of final fully equilibrium saturation of the adsorbate bed after MTZ breakthrough when the adsorbent bed reaches thermal and concentration equilibrium with the influent stream conditions over its length. As is typical in the art, the MTZ wavefront is quantified by the 5% point of the influent adsorbate concentration detected in the effluent and the 95% point of the influent adsorbate concentration detected in the effluent. High efficiency adsorbent beds have a sharp MTZ, such that there is a minimum mass of adsorbate in the effluent prior to saturation, i.e., a greater percentage of the adsorbent bed's potential adsorbent capacity is utilized than is lost in the effluent at a given point of MTZ concentration breakthrough ("BT"). Prior to MTZ breakthrough, if the adsorbent bed has residual remnants of adsorbate from previous contact with the adsorbate, such as from successive adsorption and purge steps, there may be a significant amount of breakthrough, thereby allowing the influent adsorbate to flow through the bed unimpeded.

[0225] For an unused PPAV component (i.e., containing no adsorbate at time t=0), the effluent curve typically has Fig.14 The critical point of the effluent curve occurs when the 5% influent adsorbate concentration in the effluent exceeds the initial permeate concentration, t v5％ , and the time t when the effluent adsorbate concentration reaches 95% of the difference between the initial permeate concentration and the influent adsorbate concentration v95％ , “the time to exceed 95% BT of the initial penetration”. (For an unused adsorbent bed, the penetration is approximately zero, so t v5％ Basically, 5% of the time of the influent is measured in the effluent, and t v95％ is the time at which 95% of the influent concentration is present in the effluent. v5％ According to the mass balance of the inflow rate and outflow rate of the adsorbent stream over time, the cumulative mass adsorbed by the bed is m ads,V5％ ( Fig.14 The part of the shaded area at t = 0 and t v5％ The cumulative mass of adsorbate in the effluent is m efl,V5％ The adsorption efficiency DAE for this initial period is V5％ is the amount of adsorption up to that time m ads,V5％The ratio of the total influent mass of adsorbate delivered to the adsorbent bed during the time period (e.g., m ads,V5％ With m efl,V5％ +m ads,V5％ ratio). To time t v95％ , with most of the MTZ entering the bed effluent, the cumulative mass adsorbed by the bed is m ads,V95％ ( Fig.14 The mass of adsorbate in the effluent during this period of MTZ breakthrough can be separated into two contributions: 1) the effluent mass m due to continuous penetration based on the initial permeate concentration at t = 0 efl,VB5-95％ (approximately zero for an unused adsorbent bed), and 2) the remaining effluent mass m efl,VM5-95％ , which includes the mass attributed to passing through the MTZ between 5% and 95% penetration. v95％ The total mass of the outflow during the time period is m efl,V95％ , which is equal to m efl,V5％ +m efl,VB5-95％ +m efl,VM5-95％ The sum of . From t = 0 to t v95％ The adsorption efficiency DAE of the time period V95％ is the cumulative adsorption amount up to that time m ads,V95％ and the total influent mass m of adsorbate delivered to the adsorbent bed during that time del,V95％ ratio (e.g., DAE V95％ is m ads,V95％ With m del,V95％ The ratio is equal to m ads,V95％ With m ads,V95％ +m efl,V95％ ratio).

[0226] For a PPAV component that has undergone previous steps of adsorption and purging in a dynamic adsorption test, the effluent concentration response is similar to Fig.15 , and a similar mass balance as applied to the unused PPAV component can be applied to the recycled PPAV component, and the dynamic adsorption efficiency can be similarly derived. C5％ According to the mass balance of the inflow rate and outflow rate of the adsorbent stream over time, the cumulative mass adsorbed by the bed is m ads,C5％ ( Fig.15 The part of the shaded area at t = 0 and t C5％ The cumulative mass of adsorbate in the effluent is m efl,C5％ The adsorption efficiency DAE for this initial period is C5％ is the amount of adsorption up to that time m ads,C5％ The ratio of the total influent mass of adsorbate delivered to the adsorbent bed during the time period (e.g., m ads,C5％With m efl,C5％ +m ads,C5％ ratio). To time t C95％ , with most of the MTZ entering the bed effluent, the cumulative mass adsorbed by the bed is m ads,C95％ ( Fig.15 The mass of adsorbate in the effluent during this period of MTZ breakthrough can be separated into two contributions: 1) the effluent mass m due to continuous penetration based on the initial permeate concentration at t = 0 efl,CB5-95％ (which is significantly measurable for a circulating adsorbent bed), and 2) the remaining effluent mass m efl,CM5-95％ , which includes the mass attributed to passing through the MTZ between 5% and 95% penetration, as defined by the initial penetration as the breakthrough concentration baseline. C95％ The total mass of the outflow during the time period is m efl,C95％ , which is equal to m efl,C5％ +m efl,CB5-95％ +m efl,CM5-95％ The sum of . From t = 0 to t C95％ The adsorption efficiency DAE of the time period C95％ is the cumulative adsorption amount up to that time m ads,C95％ and the total influent mass m of adsorbate delivered to the adsorbent bed during that time del,C95％ ratio (e.g., DAE C95％ is m ads,C95％ With m del,C95％ The ratio is equal to m ads,C95％ With m ads,C95％ +m efl,C95％ Taking into account the significant measurable concentration of circulating PPAV components, the permeation can be expressed in absolute mass values ​​(m efl,C5％ ) and as a measure of its contribution to the adsorption inefficiency, expressed as a mass value relative to the total butane delivered (m del,C95％ ) and relative to the total mass adsorbed (m ads,C95％ ) for comparison.

[0227] In addition to analyzing the effluent data at 5% and 95% breakthrough for the circulating PPAV to obtain penetration and efficiency, the effluent data was also analyzed at an intermediate breakthrough point of 25% influent 0.5 vol% butane (i.e., 0.125 vol% butane in the effluent) (see US2020 / 0018265A1). Fig.16 Effluent mass values ​​resulting from an intermediate breakthrough of 0.125 volume % adsorbate in the effluent are illustrated.

[0228] Determination of pore volume and surface area

[0229] The volume (PV) of pores with sizes <1.8 nm to 100 nm is measured by nitrogen adsorption porosimetry obtained by nitrogen adsorption method ISO 15901-2:2006 using a Micromeritics ASAP 2420 (Norcross, GA). The sample preparation procedure for the nitrogen adsorption test is to degas at 250°C for at least two hours, typically achieving a stable vacuum of <2 μmHg with isolated samples. The pore volume of pores with sizes <1.8 nm to 100 nm is determined from the desorption branch of the 77K isotherm of a 0.1 g sample. The nitrogen adsorption isotherm data are analyzed by the Kelvin and Halsey equations to determine the distribution of pore volumes for pore sizes with cylindrical pores according to the Barrett, Joyner and Halenda ("BJH") model. The non-ideality factor is 0.0000620. The density conversion factor is 0.0015468. The thermal evaporation hard sphere diameter is The molecular cross-sectional area is 0.162nm2. Related condensation layer thickness =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 recorded were within an absolute or relative pressure tolerance of 5 mmHg or 5%, respectively, whichever was tighter. The time between consecutive pressure readings during equilibrium was 10 seconds. Pore ​​volumes are reported based on a defined pore range, e.g. <1.8 nm in size The pore volume is PV <1.8nm .

[0230] Determination of incremental adsorption capacity

[0231] Microparticle Methods. As is known in the art, adsorption capacity can be equivalently measured by a variety of means, including volumetric, gravimetric, and dynamic (flow) methods.

[0232] The "microparticle method" is a volumetric analysis method of the gas phase mass balance of a system containing an adsorbent sample with a known volume and temperature when exposed to an adsorbate gas phase pressure change. For example, in this article, a microparticle model ASAP2020A amplification unit (Micromeritics Instrument Corporation, Norcross, GA USA) is used. By this method, as an initial state, an adsorbate gas is contained in a container with a known temperature, pressure and volume, and an adsorbate gas is contained in a container containing a second adsorbent with a known volume and temperature and a known different pressure. Then, the two container fluids are contacted by opening a connecting valve. After balancing to the final state (that is, the time sufficient for the adsorbent sample to reach thermal equilibrium and balance adsorbate absorption, as demonstrated by a stable connected system pressure), the mass balance difference of the gas phase adsorbate between the initial and final states is the mass change of the adsorbate adsorbed by the adsorbent sample. It should be noted that in all examples reported in this article, the adsorbate is n-butane.

[0233] The first step for determining IAC is sample preparation. A representative adsorbent sample is oven dried at 110C for more than 3 hours. When the apparent density value determination equally includes the mass of inert binders, fillers, and structural components in its mass numerator, the adsorbent sample should include a representative amount of any inert binders, fillers, and structural components present in the nominal volume of the adsorbent component. Conversely, when the apparent density value equally excludes the mass of inert binders, fillers, and structural components in its numerator, the adsorbent sample will exclude these inert binders, fillers, and structural components. The general conception is to accurately define the adsorption characteristics of butane based on volume within the volume.

[0234] The quartz sample tube with rubber stopper is weighed and the weight (WO) is recorded. About 0.1g of adsorbent sample is loaded into the tared sample tube and the rubber stopper is replaced. The rubber stopper is removed and the loaded sample tube is placed under the degassing hole, wherein the temperature is gradually increased to 250°C at a rate of 10°C / min. The sample is degassed at 250°C for about 2 hours. The sample is cooled and the test tube is backfilled with nitrogen. The rubber stopper is replaced and the degassed test tube is weighed (W). The dry sample weight is calculated as W-WO. The second step of the program is sample analysis. The water bath is set to 25±0.1°C. The instrument sample pressure is evacuated to less than 10μmHg (usually less than 1μmHg). The instrument stopper and sample rubber stopper are removed, and the degassed test tube is placed in the sample analysis orifice. Start the test. The instrument collected equilibrium butane isotherm data points around the following absolute pressures (mmHg): 10, 20, 30, 40, 45, 150, 300, 350, 400, 450, 600, 800, 600, 500, 450, 400, 350, 300, 150, 50, 45, 40, 35, 30, 25. The power law regression (adsorbed mass = pressure) derived from the fit of the 10, 20, 30 and 40 mmHg isotherm data points was used to calculate the adsorption capacity of butane. b ) was used to calculate the 0.5 vol% mass adsorption isotherm data points reported herein at 1 atm (3.8 mmHg).

[0235] IAC is defined as the incremental adsorption capacity between 5% and 50% n-butane at 25°C. A 5% by volume n-butane concentration (volume) at one atmosphere is provided by a balance pressure in a sample tube of 38mmHg. A 50% by volume n-butane concentration at one atmosphere is provided by a balance pressure inside a sample tube of 380mmHg. Because it may not be easy to achieve a balance at precise 38mmHg and 380mmHg, the data points collected near the target 38 and 380mmHg pressures are used to interpolate the adsorbed n-butane mass at 5% by volume n-butane concentration and 50% by volume n-butane concentration by the mass of the adsorbent sample. In the examples provided herein, this is typically performed using a linear regression of a pressure between about 300 and about 450mmHg and a pressure between about 30 and 45mmHg on the desorption branch of the isotherm. Using the ideal gas law for n-butane and the adsorbent apparent density, the IAC can then be calculated as the capacity at 50 vol % n-butane (g / g) minus the capacity at 5 vol % n-butane times the apparent density (g / L).

[0236] The McBain method is a gravimetric method. The adsorbent sample is dried at 110C for more than 3 hours. A spring is connected to the inside of the sample tube before loading onto the sample tray. Then, the sample tube is installed in the device as described. When the apparent density value determination equally includes the mass of the inert binder, filler and structural component in its mass molecule, the adsorbent sample should include a representative amount of any inert binder, filler and structural component present in the volume of the adsorbent component. Conversely, when the apparent density value equally excludes the mass of the inert binder, filler and structural component in its molecule, the adsorbent sample will exclude these inert binders, fillers and structural components. The general conception is to accurately define the adsorption characteristics of butane based on volume within the volume.

[0237] A vacuum of less than 1 Torr was applied to the sample tube, and the adsorbent sample was heated at 105°C for 1 hour. Next, the mass of the adsorbent sample was measured by the extension of the spring using a height differential gauge. The sample tube was then immersed in a temperature-controlled water bath at 25°C. Air was pumped out of the sample tube until the pressure inside the sample tube was 10 -4 Torr. n-Butane was introduced into the sample tube until equilibrium was reached at the selected pressure. Two data sets were tested for each of the four selected equilibrium pressures, obtained at about 38 Torr and obtained at about 380 Torr. 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 height gauge. The increased mass of the adsorbent sample is the amount of n-butane adsorbed by the adsorbent sample. The mass (grams) of n-butane adsorbed per unit mass (grams) of the adsorbent sample for each test was determined at different n-butane equilibrium pressures and plotted in the figure as a function of the concentration (% volume) of n-butane. A 5 volume % n-butane concentration (volume) at one atmosphere is provided by an equilibrium pressure in the sample tube of 38 Torr. A 50 volume % n-butane concentration at one atmosphere is provided by an equilibrium pressure in the sample tube of 380 Torr. Because equilibrium at exact 38 Torr and 380 Torr may not be easily achieved, the mass of n-butane adsorbed based on the mass of the adsorbent sample at 5 vol% n-butane concentration and 50 vol% n-butane concentration was interpolated from the graph using data points collected near the target 38 and 380 Torr pressures. IAC was then calculated as described herein.

[0238] Determination of effective volume characteristics

[0239] The above method is applicable to defining the nominal BWC, butane activity, IAC, and density characteristics of the adsorbent. In contrast, the effective volume of the adsorbent takes into account the air gaps, voids, and other volumes without adsorbent sandwiched between the nominal volume of the adsorbent along the vapor flow path. For example, these volumes without adsorbent include (but are not limited to) Figure 4The volume between the adsorbent volume 301 and 302, Figure 4 The volume between the adsorbent volumes 204 and 301 in (which includes the orifice 108 and the connecting conduit between tanks 101 and 300), and Figure 4 The volume between the adsorbent volumes 202 and 203 in FIG. 1 (which includes the plenum volume 107). Thus, the effective volumetric properties of the adsorbent refer to the volume average properties of the adsorbent volume that take into account air gaps, voids, and other volumes without adsorbent between the nominal volumes of adsorbent along the vapor flow path.

[0240] The effective volume (V eff ) is the nominal volume of adsorbent present along the vapor path length (V nom，i ) and the volume without adsorbent along the vapor flow path (V gap，j )

[0241] V eff =∑V nom,i +∑V gap,j

[0242] Volume adsorption characteristics of effective volume (B eff ), such as incremental adsorption capacity (g / L), apparent density (g / mL), and BWC (g / dL) are the sum of the individual properties of the individual nominal volumes considered as part of the effective volume (B nom，i ) multiplied by the nominal volume (V nom，i ), then divided by the total effective volume (V eff) :

[0243] B eff =∑(B nom,i x V nom,i ) / V eff .

[0244] Thus, the term "effective incremental adsorption capacity" is the sum of the individual nominal incremental adsorption capacities multiplied by the individual nominal volumes, and then divided by the total effective volume.

[0245] The term "effective butane working capacity (BWC)" is the sum of the individual BWC values ​​multiplied by the individual nominal volumes, and then divided by the total effective volume.

[0246] The term "effective apparent density" is the sum of the individual apparent densities multiplied by the individual nominal volumes and then divided by the total effective volume.

[0247] The term "gram-total BWC of the active volume" is the sum of the gram-total BWC values ​​(in grams) of the nominal volumes within the active volume.

[0248] In any aspect or embodiment, the specification provides a PPAV as described herein in an evaporative emission control canister system, the PPAV having an effective BWC (e.g., an effective BWC of less than about 10 g / dL or a value as described herein for BWC), an effective IAC (e.g., an effective IAC of less than about 50 g / L or a value as described herein for IAC), an effective apparent density, a gram-total BWC of effective volume, or a combination thereof.

[0249] Determination of honeycomb dimensions and cell structure

[0250] Fig. 9 is an idealized, generally schematic representation of a honeycomb cross section 600 for the purpose of illustrating key structural features, including outer edge or surface 601, parallel channels (or cells in cross section) 602, cell walls 603, and peripheral edge walls or "skins" 604. The channels have a width t c , cross-sectional area A c and perimeter P c The wall thickness of the unit is t w , and the thickness of the surface layer is t s .

[0251] To determine the dimensions of the cross section, an exemplary honeycomb component was cut into 1 mm thick slices using a diamond saw blade. The slices were then placed on a piece of white printer paper, using a ruler as a scale reference, and positioned horizontally with the horizontal and vertical axes in the camera viewfinder, with the square grid of cells at Fig. 9 The paper and sample slices were placed on a 5000K color-corrected light box with a DSLR camera (Cannon EOS Rebel T3) mounted above for photographing. The camera was located approximately 7.5 inches above the light box and was equipped with a 50mm fixed lens (1:1.8) and a 13mm extended lens tube. Multiple photos of the cross-sectional slices were taken using alternative camera positions with the slices backlit to obtain clear images. 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 of Optical and Computational Instrumentation. Pixels in the digital image are calibrated, and lines drawn on the image surface provide various measures of diameter, width, and thickness. Channel area was analyzed by the "Analyze Particles" command. Typically, image analysis was measured on slices of 1 to 5 sample portions from the same preparation batch as the portion tested for DBL emissions, with the averages of these size analysis values ​​reported in Tables 2 to 3. Figure 6 middle.

[0252] Fig.10 and Fig.11 The method for measuring the outer diameter D of the honeycomb body 600 is shown. o and inner diameter D iThe outer diameter used to calculate the component volume V and then the gram-total BWC from the component volume is measured by calipers on the same example component tested for DBL emissions (D o,卡尺 Tables 2 to 6 provide the average values ​​of the four rotation measurements D o,卡尺 The component length L was also measured by caliper.

[0253] For embodiments of slot-shaped cells with high aspect ratios, the PPAV component is characterized by measuring the channel width and wall thickness, respectively, according to its component wide and narrow channel width orientation. The x-axis refers to the measurement made in the wide width direction, as in Fig.12 For the crosshair analysis, lines 901 and 903 and in Fig.13 The channel width is oriented to be wide in the direction of lines 911 and 911 for nxn analysis (see also Fig.46 ), where all channels extend in the same horizontal direction. The y-axis refers to the measurement made in the narrow width direction, such as in Fig.12 For the crosshair analysis, lines 902 and 904 and in Fig.13 The directions of lines 912 and 914 analyzed for the nxn crop are oriented for narrow channel heights.

[0254] The inner and outer diameters t in Tables 2 to 6 s,D The surface thickness is the image analysis outer diameter D o and inner diameter D i The difference between the two diameters is the average of the four rotational measurements, i.e. D o,0° , D o,45° , D o,90° , D o,135° The average value of D i,0° , D i,45° , D i,90° , D i,135° The average value of .

[0255] Using image analysis, use the "Analyze Particles" command to obtain the total channel cross-sectional area (A c ) and perimeter (P c ). Average channel hydraulic diameter (t c,Dh ) is calculated as 4A c / P c .

[0256] Fig.12 and Fig.13 Two configurations are shown for measuring cell wall thickness by image analysis, from which the average wall thickness t is then calculated. w,avg , which is then also applied to the average cell spacing calculation. In one configuration for measuring wall thickness ( Fig.12 ), four crosshairs are drawn approximately through the center of the slice cross section, two through the middle of the cell (lines 901 and 902), and two toward the base of the cell (lines 903 and 904), with the ends of all four lines extending only through the inner walls of the peripheral cells. Intermediate cell wall thickness t w,m and base unit wall thickness t w,b is determined as the average of the wall thicknesses traversed by the intermediate cell lines 901 and 902 and the base cell lines 903 and 904, respectively. Fig.12 In the illustrative example of FIG. , each of lines 901 to 904 traverses seven channels and eight cell walls. In the second configuration for measuring wall thickness ( Fig.13 ), select a square "nxn" cell group from the cross-sectional surface, where the group does not include any peripheral cells (i.e., cells located on the outer surface). Draw four middle cell lines through the middle of the peripheral cells of the group, such as Fig.13 As shown by lines 910 to 913 in FIG. 1 , the ends of all four lines extend only through the corner channels of the peripheral cells. The wall thickness t of the nxn group w,nxn is the average of the thickness of all the walls through which the line 910 to 913 traverses. Fig.13 , each of lines 910 to 913 traverses five channels and four cell walls. For a given cross-sectional slice subjected to image analysis, the average wall thickness t in Tables 2 to 6 w,avg Calculated as t w,m ,t w,b and t w,nxn The average value of .

[0257] Channel width t c,avg Obtained from a plurality of channels in the cross section of the honeycomb body, the plurality of channels having substantially the same cross-sectional dimensions, excluding the peripheral cells. Channel width t c,avg is calculated as the channel width t c,m ,t c,b and t c,nxn The average value of Fig.12 and Fig.13 The intermediate and base units and nxn group image analysis methods are shown. For example, the channel width t c,m yes Fig.12 The average channel width of the cells crossed by the middle cell lines 901 and 902 in FIG. c,b yes Fig.12 The average channel width of the cells traversed by the base cell lines 903 and 904 in FIG. c,nxn The average cell area is calculated and the square root of the area (i.e., tc,nxn =(A c,average )^1 / 2) determines the channel width.

[0258] Cell pitch CP Dh A value of is calculated from the average channel hydraulic diameter of the entire honeycomb cross-sectional area including all cells: c,Dh Add t w,avg The second unit spacing CP tc Based on the channel widths of the plurality of channels having substantially the same cross-sectional dimensions, the plurality of channels do not include a portion of the peripheral cells. tc Yes c,avg Add t w,avg sum.

[0259] For the honeycomb PPAV example, the value of the ratio of the exterior surface to the solid volume Sv is calculated as the ratio of the total channel wall surface area (total channel perimeter x caliper length) plus the solid wall area at the two faces divided by the caliper-measured volume corrected for the void fraction ε determined by image analysis, or [(ΣP c )L+επD o,c 2 / 4] / [(1-ε)V].

[0260] Exemplary embodiments

[0261] Referring to the attached tables and figures, an example of parallel channel adsorbent volume (PPAV) is an activated carbon honeycomb prepared with a ceramic binder system and activated carbon powder, similar to the component types and process steps outlined in US 5,914,294 (incorporated herein by reference in its entirety), i.e., blending ball clay, flux, organic extrusion aid, activated carbon, calcined kaolin, followed by extrusion, drying and high temperature calcination. Comparative Examples 1 and 12a are commercially available HCA honeycomb component. Comparative Example 12b is a commercially available HCA-LBE honeycomb parts( North Charleston, South Carolina, USA). Examples 2 to 9 were prepared using RGC-PC acid activated wood-based carbon powder ( North Charleston, South Carolina, USA) and has the following characteristics: average particle size is 21.4 microns, d 10％ 3.8 μm, d 50％ 15.5 μm, d 90％ is 34.1 microns, powder butane activity (pBACT) is 44.8g / 100g, PV <1.8nmNano is 0.185cc / g, PV 1.8-5nm is 0.678cc / g, and PV 5-50nm The BET area is 1607 m 2 / g. Examples 10 and 11 were made with Sabre Thermally activated coconut-based carbon powder (Carbon Resources, Oceanside, California, USA) was prepared and had the following properties: average particle size of 18.0 μm, d 10％ 3.6 μm, d 50％ 16.3 μm, d 90％ is 39.4 microns, powder butane activity (pBACT) is 29.4g / 100g, PV <1.8nm 0.470cc / g, PV 1.8-5nm 0.114cc / g, and PV 5-50nm The BET area is 1226 m 2 / g.

[0262] In preparing exemplary PPAV honeycombs, channel width, wall thickness, and cell spacing were varied by the size and spacing of slots and pins machined into the extrusion die (see, e.g., U.S. Pat. No. 6,080,348, the entire contents of which are incorporated herein by reference in their entirety). Most of the examples were extruded with a die that formed channels having a square cross-sectional shape, with two notable comparative examples having channels having a rectangular or "slit" cross-sectional shape. The proportions of the blending ingredients, especially the proportion of activated carbon, were adjusted so that a similar range of BWC and IAC could be obtained in the finished PPAV honeycombs of the present invention and comparative examples, depending on the different void fractions in the finished part resulting from die selection. In some cases, an additional glass microsphere powder ingredient was added as a diluent to further adjust the volumetric adsorption capacity.

[0263] Table 2 provides structural performance of comparative and inventive examples of exemplary parallel channel adsorbent volumes in the form of activated carbon honeycombs of about 35 mm diameter and about 150 mm length over a BWC range of 4.1 g / dL-4.7 g / dL and an IAC range of 17 g / L-20 g / L. The table provides adsorption performance data for the examples, as well as diurnal air change loss emissions performance for the worst day (Day 2) when these examples are configured as adsorbent volumes on the vent side of a Type A evaporative emission control system. These exemplary PPAV honeycombs are cylindrical, having a circular outer cross-section measuring a diameter equal to its hydraulic diameter (equal to area / perimeter), but embodiments include PPAV honeycombs of alternative outer cross-sectional shapes whose cross-sectional dimensions are characterized by the hydraulic diameter.

[0264] Table 2. Image analysis, BWC, DBL (35x150 mm; 4.1-4.7 BWC).

[0265]

[0266]

[0267] Table 3. Image analysis, BWC, DBL - High dP Example.

[0268]

[0269]

[0270] Table 4. Image analysis, BWC, DBL, including slit-shaped unit embodiments.

[0271]

[0272]

[0273] Table 5. Image analysis of additional examples.

[0274]

[0275]

[0276] Table 6. Image analysis, BWC, DBL-PPAV tandem examples.

[0277]

[0278] As can be seen from the data in Tables 2 to 6, the inventive embodiments of the evaporative emission control system of the present invention using parallel channel adsorbents in the vent side volume have significantly reduced DBL emissions compared to using the comparative embodiments. As described above and in Table 1, the embodiments in Table 2 were tested in a vent side auxiliary canister 300 in a type A canister system in the form of an activated carbon PPAV honeycomb body having a diameter of about 35 mm and a length of about 150 mm. Fig.17 Comparative example honeycombs with average channel hydraulic diameters of 1.25 mm or greater are shown, having Day 2 DBL emissions greater than 39 mg (open symbols, ○), and appear to level off between 1.8 mm and 1.25 mm hydraulic diameters. In contrast, the inventive examples with narrower channels of 0.4 mm-0.9 mm channel hydraulic diameters have significantly lower emissions, less than 30 mg Day 2 emissions (closed symbols, ●). Fig.18It is shown that the lower emissions of the inventive examples are associated with lower cell spacings of 0.8 mm - 1.2 mm based on hydraulic diameter, particularly compared to the cell spacings of 1.6 mm - 2.2 mm for the comparative examples where the high emissions appear to have leveled off as a function of spacing.

[0279] Likewise, Fig.19 As shown, the lower emissions of the inventive examples are also associated with their multiple channel widths of approximately 0.4 mm-0.9 mm, which are much smaller than the channel widths of the comparative examples with widths greater than 1.3 mm, and their cell spacing based on the multiple channel widths is also smaller at 0.9 mm-1.2 mm, compared to the cell spacing of approximately 1.6 mm-2 mm (0.2 mm) for the comparative examples where the higher emissions appear to have leveled off as a function of spacing. Fig. 20 An alternative way to show this effect is in terms of cell density, where for the comparative examples the emissions appear to plateau between about 125 cpsi and 240 cpsi, but for the higher cell densities of the inventive examples the emissions are significantly lower ( Fig.21 ).

[0280] Surprisingly, Fig. 22 As shown, the benefit of using the inventive examples relative to the comparative examples on canister system emissions is not a result of thinner wall thickness. For example, despite having more than a two-fold difference in cell wall thickness, comparative examples 1 and 17 have identical emissions of 46 mg-47 mg. Likewise, despite falling within the same 0.27 mm-0.42 mm wall thickness range, comparative examples 1 and 16 have significantly higher emissions than inventive examples 2, 4, and 7.

[0281] It should be emphasized that there is no trend or correlation between the DBL emissions of the inventive examples and the macropore distribution and macropore volume characteristics. Fig.11 , and the macropore distribution values ​​M / M and M / m are determined according to US 9,322,368 and US 9,174,195, respectively, the entire contents of which are incorporated herein by reference. The '368 patent and the '195 patent teach that emission control performance is optimal when within the range of 30%-70% M / M and 65%-150% M / m. For example, Fig.23 As shown, the values ​​of variation for both the comparative and inventive PPAV parts in Tables 7-11 are within the same range and, therefore, are not a factor in differentiating performance for the inventive examples, similar to the similarity of composition, BWC, external dimensions, and IAC. In fact, for both exemplary groups, the M / m and M / M values ​​are often outside the taught optimal range. In terms of pore volume based on cell wall volume (normalized for differences in particle density that may result from differences in extrusion recipes), Fig.24It is shown that there is no difference in the volume of macropores between the comparative and inventive example groups for both small size (0.05 μm-1 μm) and large size (1 μm-100 μm). About 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 high volume of macropores, especially smaller size macropores, due to the ingredient formulation used in its preparation to adjust its volumetric adsorption characteristics to a range comparable to the other example groupings in Table 7).

[0282] Table 7. dP, IAC, PV (35x150 mm; 4.1-4.7 BWC).

[0283]

[0284]

[0285] Table 8. dP, IAC, PV - High dP Examples.

[0286]

[0287]

[0288] Table 9. dP, IAC, PV, including slit-shaped cell embodiments.

[0289]

[0290]

[0291] Table 10. dP, IAC, PV - Alternative BWC, Carbon and Size Examples.

[0292] Example 6 5 8 9 10 11 Comparative(C) / Invention(I) C I C I C I Caliper length (mm); L 150.0 151.5 142.5 142.6 150.7 150.6 <![CDATA[Calipers diameter (mm); D o,c > 35.0 35.0 42.2 42.3 36.0 34.4 <![CDATA[Average wall thickness (mm); t w,avg > 0.675 0.293 0.312 0.291 0.348 0.264 <![CDATA[Average channel hydraulic diameter (mm); 4ΣA c / ΣP c > 1.320 0.650 1.298 0.673 1.292 0.630 <![CDATA[Hydraulic diameter, unit spacing (mm); CP Dh > 1.995 0.943 1.610 0.963 1.640 0.894 <![CDATA[Multiple width unit spacings (mm); CP tc = t c,avg + t w,avg > 2.056 0.960 1.676 0.978 1.715 0.911 <![CDATA[Unit density (cpsi); n c / (πD o 2 / 4)]]> 150 660 230 669 227 733 dP at 40lpm, kPa 0.074 0.281 0.035 0.249 0.054 0.264 dP at 46cm / s, kPa 0.065 0.261 0.034 0.247 0.054 0.250 IAC, g / L 26.3 24.6 10.4 10.4 9.9 10.0 5% butane capacity (g / g); m5% 0.068 0.069 0.068 0.040 0.121 0.054 50% butane capacity (g / g); m50% 0.115 0.115 0.109 0.065 0.151 0.070 Ratiom0.5% / m50% 0.331 0.332 0.359 0.338 0.577 0.559 Ratiom5% / m50% 0.593 0.594 0.621 0.610 0.801 0.783 Particle density <100μm,cc / g 1.304 1.024 0.745 0.972 0.896 1.543 <![CDATA[BET surface area, m 2 / g]]> 433 444 407 250 588 276 <![CDATA[PV <1 . 8nm ,cc / g]]> 0.059 0.058 0.056 0.031 0.225 0.099 <![CDATA[PV 1.8-5nm ,cc / g]]> 0.167 0.173 0.169 0.108 0.053 0.035 <![CDATA[PV 5-50nm ,cc / g]]> 0.101 0.112 0.075 0.048 0.017 0.009 <![CDATA[PV <0.1μm ,cc / g]]> 0.337 0.362 0.305 0.191 0.303 0.145 <![CDATA[PV 0.1-100μm ,cc / g]]> 0.163 0.156 0.454 0.406 0.351 0.230 <![CDATA[PV 0.05-1mm ,cc / g]]> 0.220 0.206 0.427 0.407 0.331 0.215 <![CDATA[PV 1-100mm ,cc / g]]> 0.012 0.021 0.049 0.032 0.032 0.022 <![CDATA[PV 0.05-0.5μm ,cc / g]]> 0.219 0.205 0.189 0.200 0.250 0.148 <![CDATA[PV 0.05-100μm ,cc / g]]> 0.233 0.227 0.476 0.438 0.363 0.237 <![CDATA[PV 0.05-1μm / PV 0.05-100μm ,%]]> 94.6％ 90.9％ 89.7％ 92.8％ 91.2％ 90.6％ <![CDATA[PV 0.05-0.5μm / PV 0.05-100μm ,"M / M"]]> 94.0％ 90.3％ 39.7％ 45.7％ 68.9％ 62.5％ <![CDATA[PV 0.1-100μm / PV <0.1μm ,"M / m"]]> 48.3％ 42.9％ 149％ 212％ 116％ 158％ <![CDATA[PV 0.05-1μm ,cc / cc-wall]]> 0.169 0.202 0.572 0.419 0.369 0.139 <![CDATA[PV 1-100μm ,cc / cc-wall]]> 0.010 0.020 0.066 0.033 0.035 0.014

[0293] Table 11. dP, IAC, PV-PPAV tandem examples.

[0294]

[0295]

[0296] In seeking to account for the lower emissions from the inventive embodiments, the flow restriction effect of the PPAV component in the auxiliary tank was considered and found to only partially explain the overall improvement. In one set of experiments, by placing the orifice plate "before" the PPAV component of Example 1 ( Figure 5 as Comparative Example 18, or by placing the orifice plate "after" the PPAV component of Example 1 ( Figure 5 Example 18 and 19 were tested in the same manner as Example 1 in Table 7, and the DBL emissions were measured. Fig.25 As shown, the orifice plates present in Examples 18 and 19 have some benefit of increased flow restriction compared to Example 1 without the orifice plates, but the high cell density, low cell spacing inventive Examples 2 to 4 and Example 7, which have equivalent dimensions and adsorption characteristics to Example 1, consistently show lower emissions, meaning that their benefits outweigh any small benefit attributable to the flow restriction effect. In another experiment with the flow restriction effect, a PPAV (Example 14) was prepared having a 1.6 mm cell spacing dimension similar to Example 1, but through the use of an alternative extrusion die and modification of the formulation, with smaller parallel channel channels and thicker cell walls, so that the net volume adsorption characteristics are approximately the same as Example 1 and the other examples in Table 2. The result of the thick wall extrusion is an example with high flow restriction at the 1.6 mm cell spacing of the comparative example, but with a channel width of the dimensions of the inventive examples. As shown Fig.25 As shown, the percolation emissions for thick cell wall Example 14 follow the trend of the slightly lower emissions for Examples 18 and 19, allowing the lower emissions to be attributed to its higher flow restriction performance (and it is noteworthy that despite the cell wall thickness being almost four times greater, the emissions for Example 14 are also lower than for Example 1). In addition, despite the narrower channel width of Example 14, its percolation emissions do not have as low emissions as the inventive examples of similar channel width but with low spacing, which reinforces the particular importance of the low cell spacing and high cell density of the inventive examples to the emissions performance (see Fig.26 ).

[0297] Additional testing revealed the unexpected importance of low spacing and small hydraulic diameter of the channels for low emissions in PPAV components with only partially multiple low cell spacing and only partially multiple narrow channel widths, which are provided by channels with high aspect ratio shapes (e.g., slit-shaped channels). Examples 24 and 25 with slit-shaped channels (rectangular shaped units with a long side length four or three times the length of the short side) in a 4:1 and 3:1 ratio were prepared using special molds, respectively, where the short channel side was approximately 1 mm long (see Tables 4 and 9). These slit-shaped channel components are in the form of integral pieces of 29 mm diameter x 150 mm length, with a BWC of approximately 4.3 g / dL. (Note: the wall thickness value used to determine the hydraulic diameter cell spacing is the average of the x and y wall thicknesses). Although the total cell density of 166 cpsi-179 cpsi and the cell spacing and channel width characteristics based on hydraulic diameter are similar to the other comparative examples, the cell spacing perpendicular to the short direction (1.2 mm-1.5 mm) is much shorter than the comparative examples. Similar size and BWC components with square channels of 234 cpsi and 441 cpsi cell densities (Examples 22 and 23, respectively) were also prepared and tested in the tank system ( Fig. 27 The tank system data show that the slit channel embodiments 24 and 25 have unexpectedly high discharges compared to both square channel embodiments 22 and 23, where the discharge trends of the slit channel embodiments 24 and 25 follow their cell spacing or hydraulic diameter cell spacing characteristics based on average width rather than their narrow channel characteristics (see Fig.28 and Fig.29 ).

[0298] For embodiments with conventional 1.6 mm cell spacing, there is a consistent trend of having lower emissions with low spacing embodiments over a wide range of adsorption characteristics in the same type A tank system compared to embodiments with lower cell spacing but otherwise equivalent external dimensions and adsorption characteristics (BWC, IAC). Fig.30 and Fig.31Lower emissions are shown over a wider range of BWC and IAC, respectively. In both figures, the comparative example data points at 1.6 mm cell have otherwise equivalent examples at lower cell spacings, including the following (examples of 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 lower cell spacing (about 1 mm based on multiple channel widths or average channel hydraulic diameters compared to about 1.6 mm-1.7 mm) and smaller channel openings (about 0.7 mm based on multiple channel widths or average channel hydraulic diameters compared to about 1.3 mm-1.4 mm), Example 9 as an adsorbent volume filling in an auxiliary tank in an A-type tank had 8 mg DBL Day 2 emissions, which is 73% lower than the emissions of about 29 mg using Example 8 as the adsorbent volume filling of the auxiliary tank. Comparative Example 10 and Inventive Example 11 were prepared using highly microporous coconut-based carbon powder instead of mesoporous wood-based carbon powder, and the resulting PPAV honeycombs had similar dimensions of about 35 mm diameter and 150 mm length, similar BWC of about 3 g / dL, and similar IAC of about 10 g / L; however, due to the lower pitch (about 0.9 mm for multiple channel widths or average channel hydraulic diameters compared to about 1.6 mm-1.7 mm) and smaller channel spacing (about 0.6 mm based on multiple channel widths or average channel hydraulic diameters compared to about 1.3 mm-1.4 mm), Example 11 as an adsorbent volume filler in an auxiliary tank in an A-type tank system had about 17 mg DBL Day 2 emissions, which is about half of the emissions of about 34 mg produced using Example 10 as the adsorbent volume filler for the auxiliary tank. Comparative Examples 1 and 6 have a length of 35 mm x 150 mm relative to Inventive Examples 2 to 5 and Example 7, have a BWC of 4.2 g / dL-5.9 g / dL and an IAC of 17 g / L-26 g / L (Tables 2 and 3), and have similar cell spacing, channel width, and discharge comparisons and contrasts as the above-mentioned Examples 8 to 11.

[0299] In the examples, embodiments with smaller cell spacing and smaller channel widths are utilized. Unexpectedly, the PPAV described herein exhibits greater tank simplicity, lower flow restriction, and lower DBL emissions. For example, Comparative Examples 12a and 12b are commercially available PPAV honeycomb bodies. HCA and HCA-LBE parts were obtained, with a diameter of about 29 mm and a length of 100 mm, with a conventional cell pitch of 1.6 mm-1.7 mm and a channel width of 1.2 mm-1.3 mm, and tested as a series pair combination in a B-type canister system (Example 12a+bB) to achieve a DBL Day 2 emission of <20 mg (12.4 mg). The canister system is configured in this way in some vehicle platforms with multiple PPAV honeycombs in series to meet emission requirements, with one part having a BWC of about 4 g / dL-4.5 g / dL and another part in parallel with a BWC of less than 3 g / dL, located closest to the system vent, which is particularly needed when advanced engine technologies (e.g., hybrid vehicles, GDI engines, start / stop and turbo-assisted engines) only provide a small amount of purge. By comparison, in the auxiliary tank of the B-type tank system, the inventive Example 9B, which has a much smaller pitch of about 1 mm and a smaller channel width and hydraulic diameter of less than 0.7 mm than Examples 12a or 12b, has an emission of 9 mg, which is 24% lower than the paired conventional PPAV honeycomb Example 12a+bB. Clearly, while both Examples 9B and 12a+bB have DBL Day 2 emissions <20 mg, Example 9B allows for tank system B with significantly lower emissions with a single PPAV honeycomb in place to increase design simplicity, and in addition has a 25% smaller system load flow restriction at 40 slpm (1.18 kPa) than Example 12a+bB and a 22% smaller system purge flow restriction at 40 slpm (1.90 kPa) than Example 12a+bB, allowing for greater flexibility in tank system design choices (e.g., screens, filters, valves, conduits, etc.) that affect flow restriction.

[0300] Embodiments were also tested in tank systems challenged with a wide range of purge volumes, demonstrating consistent benefits over comparative examples from low cell pitch and low channel width as the purge amount was reduced. Fig.32 and Fig.33 The consistently lower Day 2 DBL emissions for Inventive Example 4 relative to Comparative Example 1 are shown when placed in a 2.1 L LEV II A type tank system as a PPAV component and tested over the range of 210 L - 310 L and 94 BV - 138 BV (see also Table 12).

[0301] Table 12. Purge Effects - LEV II System.

[0302]

[0303] Another set of experiments on the effect of purge volume on the emission performance of DBL was conducted with Figure 8 The commercial LEVIII canister system with adsorbent volumes configured as a C-type canister system as shown in , wherein two PPAV honeycomb components (comprising volumes 502 and 504 of Comparative Examples 21a and 21b) were present in series on the vent side. In these tests, the canister system was tested as-received and then retested with volumes 502 and 504 of the inventive example PPAV honeycombs (Examples 20a and 20b) exchanged with the same external dimensions and adsorption characteristics (BWC and IAC) as each of the two original as-received components. Fig.34 , Fig.35 As shown in Table 13, the results are very significant for this tank system. For example, at higher purge levels of 186-211 L and 71-81 BV, there is only a small difference between the emissions of the original comparative examples, where the lower emissions of several mg for Inventive Example 20a+bC are 44%-47% of the results for Comparative Example 21a+bC. However, at lower purges, the difference becomes increasingly larger, as low as 19% of the comparative results at 52 BV purge, where the emissions for Inventive Example 20a+bC are about 18 mg and the emissions for Comparative Example 21a+bC are 97 mg. This low level of emissions is important because the BETP emissions target for LEVIII is <20 mg for tank systems, and the prior art has noted that meeting the LEVIII evaporative emissions target is extremely difficult when less than 50 BV-80 BV of purge is available, especially close to <50 BV of purge (see US2011 / 0168025 Al, US 9,657,691, JSAE 20077051 / SAE 2007-01-1929, and Tank tech 2015, Trends for Fuel Subsystems (Part 1), "Low Bleed Solutions Meeting LEVIII / Tier 3 Evaporative Emission Standards", all of which are incorporated herein by reference in their entirety). In the case of very low purge, common sense dictates that more extreme approaches are necessary to meet emissions, including adding heating or heat exchanger functionality to the tank system, or even adopting a sealed fuel tank system to prevent diurnal losses. However, it is apparent from these test data that using PPAV adsorbent volumes with low cell spacing and small channel widths as described herein surprisingly and unexpectedly allows low emission targets to be met without the need for heaters or sealed boxes.

[0304] Table 13. Purge Effects - LEVIII System - CR-V.

[0305]

[0306] While the art teaches that higher cell density (higher number of cells per unit cross-sectional area, or lower distance between cells) of a PPAV monolith will result in a sharper mass transfer zone (MTZ) and result in more efficient saturation of the adsorbent volume under dynamic flow adsorption, a surprising lack of any such MTZ or efficiency advantage was observed for the cell densities or cell spacings tested when the disclosed methods of measuring the mass transfer zone were applied, either for saturation of a virgin component or for saturation of a component after an adsorption-purge pretreatment regimen. Surprisingly, the ranges of cell density and cell spacing were observed to provide benefits on DBL emissions for the inventive embodiments, including the lack of any such MTZ or efficiency effects for PPAVs tested at cell densities or cell spacings both outside and within the inventive ranges described herein.

[0307] As shown by Rezaei and Webley (2009) for CO2 adsorption with virgin monoliths, the expected effect is a symmetrical pivoting sharpening of the breakthrough curve for the adsorbate with increasing cell density, with less adsorbate mass in the effluent stream before saturation. However, for n-butane adsorption, the cell density effect appears to disappear at about 200 cpsi. Valdes-Solis et al. (2004) showed similar widths of the 5%-95% breakthrough curves for the same 150 mm total length cross-sectional monolith when comparing cell densities of 200 cpsi and 400 cpsi. In the virgin state, dynamic adsorption tests of Comparative Examples 1 and Comparative Examples 15 to 17 and Inventive Examples 2 to 4 and Inventive Example 7 showed that the MTZ breakthrough sharpened as the cell density increased from 30 cpsi, with a cell spacing based on hydraulic diameter of about 4 mm (Example 15), however, the sharpening of the MTZ gradually decreased with increasing cell density and decreasing cell spacing. The notable aspect of these examples from this comparison is that these examples have approximately the same external dimensions, BWC and carbon composition characteristics, and differ only in the cell structure, i.e., channel size and spacing. For Example 15, 95% saturation (DAE V95％ ) has a dynamic adsorption efficiency of about 50%, and then through a cell density of about 200 cpsi ( Fig.36 ) and a cell pitch of approximately 2 mm ( Fig.37 ) reaches an efficiency plateau of about 60%-70%. Therefore, any benefit of the embodiments of the inventive embodiments in terms of canister system emissions performance cannot be predicted from the dynamic adsorption MTZ and efficiency behavior of the unused components (see Tables 14 to 17).

[0308] Table 14. Dynamic adsorption test - 35x1504.1-4.7BWC.

[0309]

[0310]

[0311]

[0312] Table 15. Dynamic Sorption Testing - High dP Examples.

[0313]

[0314]

[0315] Table 16. Dynamic Adsorption Testing - Alternative BWC, Carbon and Size.

[0316]

[0317]

[0318] A potentially more relevant performance predictor for a PPAV monolith intended for cyclic applications (such as evaporative emissions control) may be the dynamic adsorption MTZ characteristics after the PPAV monolith has been cycled through adsorption and purge pretreatments, as taught in US2020 / 0018265. When this test was applied to Examples 1 to 4, 7, and 15 to 17, which have approximately the same external dimensions, BWC, and carbon composition characteristics, there is a convergence in the breakthrough MTZ as the cell density increases from its lowest value (e.g., the cell spacing decreases from its highest value). For example, there is significant early breakthrough and early saturation for the lowest cell density PPAV (Example 15), which is attributed to the lack of effectiveness of the purge pretreatment in regenerating its carbon due to its wide channel width, and gives a low cyclic dynamic adsorption efficiency of only about 45% to 95% saturation (DAE C95％ ). As the cell density and cell pitch increase in the embodiment, DAE C95％ The cell density increases to about 55%-65% with a cell density of about 200 cpsi and a cell spacing of about 2 mm (see Fig.38 and Fig.39 ), while the inventive examples have no different dynamic adsorption efficiency behavior. Considering the abbreviated metric of 25% saturation (0.125 vol% n-butane effluent for 0.5 vol% influent) described in US2020 / 0018265, according to the unit density ( Fig.40 ) and cell spacing ( Fig.41 ), also in dynamic adsorption DAE C 25％satThere is a plateau in the , and again the dynamic adsorption efficiency behavior is not differentiated by the inventive examples. As a measure of the impact on system capacity, the canister systems containing the comparative examples or the inventive examples show no difference in GWC, with the adsorption cycle endpoint being triggered by the cumulative breakthrough mass emanating from the vent side PPAV volume (see Fig.45 ). Therefore, in practice, within a canister system, the effect of the high cell density, low cell spacing of a PPAV component on the vent side of the system is limited to the emissions performance of the system on which the PPAV component is mounted, without any significant benefit or detriment to the operating capacity of that system, which is consistent with the lack of different dynamic adsorption properties of the independent PPAV components.

[0319] Table 17. Dynamic adsorption test including slit-shaped cell.

[0320]

[0321]

[0322] Alternatively, the permeate emission component (m efl,C5％ ) can be considered a potential predictor of diurnal ventilation loss emissions encountered by tank systems containing PPAV components during BETP testing. However, this correlation is not obvious. For example, when comparing Comparative Example 1 and Comparative Examples 15 to 17 with Inventive Examples 2 to 4 and Inventive Example 7, when considering the mass ( Fig.42 ), percentage of total inflow before 95% MTZ penetration ( Fig.43 ) or the percentage of the total mass loaded before 95% MTZ penetration ( Fig.44 ) , the difference between the inventive example and the comparative example for 5% penetration m efl,C5％ There was no discernible difference in the permeate quality before and after the addition of the PPAV components. Therefore, the performance of the PPAV component as a bulk component of the adsorbent within a canister system cannot be predicted from the available test methods for dynamic adsorption (see Tables 14 through 17). In fact, in special comparative tests where the vapor challenge imposed on the vent-side PPAV was measured during the air change loss step of the BETP test, the challenge to the auxiliary canister containing the PPAV actually increased for systems with increased cell density of the PPAV component and decreased cell spacing. In these tests using a Type A canister system, the PPAV component was removed just prior to the DBL portion of the BETP protocol ( Figure 5As shown in Table 18, during the second day of the DBL portion of the BETP protocol (in repeated experiments conducted for each embodiment, but the DBL emission step of the BETP protocol was conducted with the auxiliary tank 300 removed), the vapor load imposed by the main tank surprisingly increased approximately linearly with the unit density of the PPAV components that had been installed in the auxiliary tank during the previous preparation step, which means that despite the additional vapor load challenge, the system with the inventive embodiment provides a system with low emission performance.

[0323] Table 18. Examples of removal of PPAV.

[0324]

[0325] While not being bound by theory, it appears that one central factor is bulk mass transfer within the channels of the PPAV monolith, where narrow channel dimensions are advantageous, as provided by high cell density. However, narrow channel widths do not appear to be sufficient to achieve low emissions effects (see Examples 14, 24, and 25). A second factor appears to be additionally sufficient total open area, as also provided by high cell density, so that the velocity of the gas flow through the PPAV component at some point in the cycle is not excessive, and so that there is sufficient residence time (see Example 14 which has a relatively narrow channel width, but also has insufficient open area from conventional cell density and spacing). Nonetheless, it is clear from the inventive examples that the following embodiments teach a method for obtaining unexpectedly low percolation emissions with an evaporative emission canister system, even when the purge volume is very small. Furthermore, the surprising effect on the DBL emissions of the canister system could not have been predicted by existing testing of the performance and dynamic performance of the individual PPAV components.

[0326] The contents of all references, patents, pending patent applications, and issued patents cited throughout this application are expressly incorporated herein by reference.

[0327] A person skilled in the art will recognize or be able to determine many equivalents of the specific embodiments described herein using only routine experiments. Such equivalents are intended to be covered by the appended claims. It should be understood that the detailed examples and embodiments described herein are given only for illustrative purposes and are by no means considered to be limitations of the present invention. Various modifications or changes thereto will be considered by a person skilled in the art, and are included in the essence and scope of the present application and are considered to be within the scope of the appended claims. For example, the relative amount of the ingredients can be changed to optimize the desired effect, other ingredients can be added, and / or one or more of the ingredients can be replaced with similar ingredients. Other advantageous features and functions associated with the system, method and process of the present invention will be apparent from the appended claims. In addition, a person skilled in the art will recognize or be able to determine many equivalents of the specific embodiments of the present invention described herein using only routine experiments. Such equivalents are intended to be covered by the appended claims.

Claims

1. An evaporative emission control canister system, the evaporative emission control canister system comprising: one or more canisters, the one or more canisters comprising a fuel side adsorbent volume and at least one vent side parallel channel adsorbent volume PPAV, wherein the at least one vent side PPAV comprises an exterior surface and a plurality of parallel channels or channels extending therethrough parallel to the exterior surface, and The parallel channels or channels are configured to have an average channel hydraulic diameter (t c，Dh ), hydraulic diameter unit spacing (CP) less than or equal to 1.5 mm Dh ) or at least one of their combinations.

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

3. The evaporative emission control canister system of claim 1 or 2, wherein the hydraulic diameter unit spacing (CP Dh ) is less than or equal to 1.45mm.

4. The evaporative emission control canister system of any one of claims 1 to 3, wherein the PPAV further comprises at least one of the following: (i) a plurality of channel widths (t c，avg ); (ii) multiple channel width cell pitch (CP) less than 1.5 mm tc，avg ); (iii) a cell density of 285 cpsi to 1000 cpsi; (iv) a cell wall thickness of less than 0.5 mm; (v) a BWC of less than 10 g / dL; (vi) an incremental adsorption capacity of less than 50 g / L at 25° C. under n-butane between 5% and 50%; or (vii) a combination thereof.

5. The evaporative emission control canister system of claim 4, wherein the plurality of channel widths (t c，avg ) is less than 1.20mm.

6. The evaporative emission control canister system of claim 4 or 5, wherein the plurality of channel width unit pitches (CP tc，avg ) is less than 1.45mm.

7. The evaporative emission control canister system of any one of claims 4 to 6, wherein the cell density is from 300 cpsi to 900 cpsi.

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

9. The evaporative emission control canister system of any one of claims 4 to 8, wherein the at least one vent-side PPAV has a BWC of less than 9.5 g / dL.

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

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

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

13. The evaporative emission control canister system of any one of claims 1 to 12, wherein the at least one vent-side PPAV comprises an adsorbent material derived from at least one of wood, wood chips, wood flour, cotton linters, peat, coal, coconut, lignite, carbohydrates, petroleum pitch, petroleum coke, coal tar pitch, fruit pits, nut kernels, 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 one of claims 1 to 13, wherein the at least one vent-side PPAV comprises activated carbon or charcoal.

15. The evaporative emission control canister system of any one of claims 1 to 14, wherein the system has a two-day diurnal air loss (DBL) of no more than 50 mg at no more than 315 liters of purge or no more than 150 bed volumes (BV) of purge applied after the 40 g / hr butane loading step.

16. An evaporative emission control system, the evaporative emission control system comprising: A fuel tank, the fuel tank being used to store fuel; an engine having an air induction system and adapted to consume the fuel; as well as One or more tanks, the one or more tanks comprising a fuel side adsorbent volume and at least one vent side parallel channel adsorbent volume PPAV, wherein the at least one vent side PPAV comprises an exterior surface and a plurality of parallel channels or channels extending therethrough parallel to the exterior surface, and wherein the parallel channels or channels are configured to have an average channel hydraulic diameter (t) less than or equal to 1.25 mm. c，Dh ), hydraulic diameter unit spacing (CP) less than or equal to 1.5 mm Dh ) or at least one of their combinations, wherein the canister includes 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 allowing purge air to enter 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 toward the at least one PPAV and the vent conduit to the fuel side adsorbent volume, and by an air flow path from the vent conduit toward the fuel side adsorbent volume and the fuel vapor purge outlet to the at least one PPAV.

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

18. The evaporative emission control canister system of claim 16 or 17, wherein the hydraulic diameter unit spacing (CP Dh ) is less than or equal to 1.45mm.

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

20. The evaporative emission control canister system of claim 19, wherein the plurality of channel widths (t c，avg ) is less than 1.20mm.

21. The evaporative emission control canister system of claim 19 or 20, wherein the plurality of channel width unit spacings (CP tc，avg ) is less than 1.45mm.

22. The evaporative emission control canister system of any one of claims 19 to 21, wherein the cell density is from 300 cpsi to 900 cpsi.

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

24. The evaporative emission control canister system of any one of claims 19 to 23, wherein the at least one vent-side PPAV has a BWC of less than 9.5 g / dL.

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

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

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

28. The evaporative emission control canister system of any one of claims 16 to 27, wherein the at least one vent-side PPAV comprises an adsorbent material derived from at least one of wood, wood chips, wood flour, cotton linters, peat, coal, coconut, lignite, carbohydrates, petroleum pitch, petroleum coke, coal tar pitch, fruit pits, nut kernels, 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 one of claims 16 to 28, wherein the at least one vent-side PPAV comprises activated carbon or charcoal.

30. The evaporative emission control canister system of any one of claims 16 to 29, wherein the system has a two-day diurnal air loss (DBL) of no more than 50 mg at no more than 315 liters of purge or no more than 150 bed volumes (BV) of purge applied after the 40 g / hr butane loading step.

31. An evaporative emission control canister system, the evaporative emission control canister system comprising: one or more tanks, the one or more tanks comprising a fuel-side adsorbent volume; as well as One or more vent-side PPAVs, the one or more vent-side PPAVs comprising an outer surface and a plurality of parallel channels or channels extending therethrough parallel to the outer surface, and wherein the parallel channels or channels are configured to have an average channel hydraulic diameter (t less than or equal to 1.25 mm) c，Dh ), hydraulic diameter unit spacing (CP) less than or equal to 1.5 mm Dh ) or a combination thereof, and at least one of the following: (i) Multiple channel widths (t c，avg ); (ii) Multiple channel width cell pitches (CP) less than 1.5 mm tc，avg ); (iii) a cell density of 285 cpsi to 1000 cpsi; (iv) a cell wall thickness of less than 0.5 mm; (v) BWC less than 10 g / dL; (vi) an incremental adsorption capacity of less than about 50 g / L at between 5% and 50% n-butane at 25°C; or (vii) combinations thereof, wherein the fuel side adsorbent volume and the PPAV are in vapor or gas communication and define a vapor flow path that allows air and / or fuel vapor to flow or diffuse therethrough, and wherein the evaporative emission control canister system has a two-day diurnal air loss (DBL) of no more than 50 mg at no more than 315 liters of purge or no more than 150 bed volumes (BV) of purge applied after the 40 g / hr butane loading step.

32. The evaporative emission control canister system of any one of claims 1 to 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 less than about 50 g / L at between 5% and 50% n-butane at 25°C, or a combination thereof.

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