U.S. patent number 10,843,117 [Application Number 15/989,849] was granted by the patent office on 2020-11-24 for active carbon filter for a carbon canister and a method for producing the same.
This patent grant is currently assigned to Ford Motor Company. The grantee listed for this patent is Ford Motor Company. Invention is credited to Syed K Ali, Seyyed Mohsen Mousavi Ehteshami, Zhuoyuan Li, Sami Siddiqui, Mohammad Usman.
United States Patent |
10,843,117 |
Ehteshami , et al. |
November 24, 2020 |
Active carbon filter for a carbon canister and a method for
producing the same
Abstract
A method for producing an active carbon filter for a carbon
canister includes defining a body having a honeycomb structure with
a plurality of bleed passages from a polymer based material, and
forming an adsorption layer along a surface of the body, where the
adsorption layer is made of a carbon based material.
Inventors: |
Ehteshami; Seyyed Mohsen
Mousavi (San Diego, CA), Usman; Mohammad (Northville,
MI), Siddiqui; Sami (Canton, MI), Li; Zhuoyuan
(Dearborn, MI), Ali; Syed K (Dearborn, MI) |
Applicant: |
Name |
City |
State |
Country |
Type |
Ford Motor Company |
Dearborn |
MI |
US |
|
|
Assignee: |
Ford Motor Company (Dearborn,
MI)
|
Family
ID: |
1000005200184 |
Appl.
No.: |
15/989,849 |
Filed: |
May 25, 2018 |
Prior Publication Data
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|
|
|
Document
Identifier |
Publication Date |
|
US 20190358576 A1 |
Nov 28, 2019 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B01J
20/324 (20130101); B01J 20/3007 (20130101); B01J
20/28045 (20130101); F02M 25/0854 (20130101); B01J
20/3208 (20130101); B01D 53/0407 (20130101); B01J
20/26 (20130101); B01J 20/20 (20130101); B01J
20/3078 (20130101); B01D 2253/25 (20130101); B01D
2253/102 (20130101); B01D 2253/3425 (20130101) |
Current International
Class: |
B01D
53/04 (20060101); F02M 25/08 (20060101); B01J
20/32 (20060101); B01J 20/30 (20060101); B01J
20/28 (20060101); B01J 20/26 (20060101); B01J
20/20 (20060101) |
Field of
Search: |
;95/146 ;96/154 ;123/519
;428/116 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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H08188489 |
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Jul 1996 |
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JP |
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2007/063608 |
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Jun 2007 |
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WO |
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Other References
Surface Coating of Plastic Parts for Business Machines, U.S.
Environmental Protection Agency, 1986. cited by applicant .
Andrew Ng MH, Hartadi LT, Tan H, Patrick Poa CH, "Efficient coating
of transparent and conductive carbon nanotube thin films on plastic
substrates." Nanotechnology, 19 (2008) 205703. cited by applicant
.
Cunman Zhang, Zhen Geng, Jianxin MA, "Self-assembly synthesis of
ordered mesoporous carbon thin film by a clip-coating technique."
Microporous and Mesoporous Materials 170 (2013) 287-292. cited by
applicant .
Alessandra Mosca, Jonas Hedlund, Paul A.Webley, Mattias Grahn,
Fateme Rezaei, "Structured zeolite NaX coatings on ceramic
cordierite monolith supports for PSA applications." Microporous and
Mesoporous Materialsvol. 130, Issues 1-3, May 2010, pp. 38-48.
cited by applicant .
M.A. Ulla, R. Mallada, J. Coronas, L. Gutierrez, E. Miro', J.
Santamari'a, "Synthesis and characterization of ZSM-5 coatings onto
cordierite honeycomb supports" Applied Catalysis A: General 253
(2003) 257-269. cited by applicant .
Ling Huang, Zhonghua Xiang, and Dapeng Cao, "A porous diamond
carbon framework: a new carbon allotrope with extremely high gas
adsorption and mechanical properties." Journal of Materials
Chemistry A 2013,1, 3851-3855. cited by applicant.
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Primary Examiner: Lawrence, Jr.; Frank M
Attorney, Agent or Firm: Burris Law, PLLC
Claims
What is claimed is:
1. A method for producing an active carbon filter for a carbon
canister, the method comprising: defining a body having a honeycomb
structure with a plurality of bleed passages from a polymer based
material; and forming an adsorption layer along a surface of the
body, wherein the adsorption layer is made of a carbon based
material, wherein defining the body comprises: forming a plurality
of substrates, wherein each of the substrates defines a plurality
of channels extending along a first axis, and stacking the
plurality of substrates along a second axis perpendicular to the
first axis to define the body having the honeycomb structure,
wherein the adsorption layer is formed along the surface of each of
the substrates, and wherein the adsorption layer is formed on each
surface of the substrates before the substrates are stacked.
2. The method of claim 1 further comprising housing the body
defined by the substrates and having the adsorption layer in a
case, the case having a polymer based core with a supplemental
adsorption layer disposed along the surface of the core.
3. The method of claim 1, wherein the substrates are formed using
injection molding.
4. The method of claim 3, wherein the forming the adsorption layer
further comprises, for each of the substrates, depositing the
carbon based material along the surface of the substrate, wherein
the substrates are stacked after the adsorption layer is formed on
the substrates.
5. The method of claim 1, wherein: the defining the body further
comprises injection molding the body using a first material made of
the polymer based material and a second material made of the carbon
based material, and the forming the adsorption layer further
comprises sintering the body made of the first and second materials
to expose the carbon based material along the surface of the
body.
6. The method of claim 1, wherein the adsorption layer is formed
using one of the following procedures: dip-coating, seeding and in
situ growth, or plasma coating.
7. The method of claim 1, wherein the thickness of the adsorption
layer is between 10 .mu.m to 100 .mu.m.
8. An active carbon filter comprising: a body defining a honeycomb
structure with a plurality of bleed passages, wherein the body is
defined by a polymer based material; an adsorption layer disposed
along a surface of the body, wherein the adsorption layer is
defined by a carbon based material, and a case housing the body,
wherein the case has a core defined by the polymer based material
and a supplemental adsorption layer defined by the carbon based
material and disposed along a surface of the core.
9. The active carbon filter of claim 8, wherein: the body is
defined by a plurality of substrates, each of the substrates
defines a plurality of channels extending along a first axis, and
the substrates are arranged in a stacked configuration along a
second axis perpendicular to the first axis to define the body
having the honeycomb structure, and the adsorption layer is
disposed along the surface of each of the substrates.
10. A carbon canister comprising one or more of the active carbon
filters of claim 8.
11. A method for producing an active carbon filter for a carbon
canister, the method comprising: defining a body having a honeycomb
structure with a plurality of bleed passages extending along a
first axis, wherein the body is formed from a polymer based
material; forming an adsorption layer along an entire surface of
the body, wherein the adsorption layer is made of a carbon based
material, wherein defining the body comprises: forming a plurality
of substrates, wherein each of the substrates defines a plurality
of channels extending along a first axis, and stacking the
plurality of substrates along a second axis perpendicular to the
first axis to define the body having the honeycomb structure, and
wherein the adsorption layer is formed on each surface of the
substrates before the substrates are stacked.
12. The method of claim 11, wherein the substrates are formed using
injection molding.
13. The method of claim 11, wherein the forming the adsorption
layer further comprises, for each of the substrates, depositing the
carbon based material along the surface of the substrate, wherein
the substrates are stacked after the adsorption layer is formed on
the substrates.
Description
FIELD
The present disclosure relates to an active carbon filter for a
carbon canister of a vehicular evaporative emission control
system.
BACKGROUND
The statements in this section merely provide background
information related to the present disclosure and may not
constitute prior art.
Vehicles having internal combustion engines generally include an
evaporative emission control (EEC) system to block or capture
hydrocarbons from, for example, diurnal emissions, refueling
emission, permeation, and/or other evaporative emissions. Diurnal
emission is caused by the evaporation of gasoline within a gas tank
due to changes in temperature throughout the day, the refueling
emission occurs as gasoline is pumped in the tank, and permeation
occurs when a polymer based component of the fuel system is
saturated with fuel.
In addressing the various evaporative emissions, the EEC system
includes a carbon canisters that includes active carbon elements,
such as carbon pellets and filters, to draw in and store the
hydrocarbons. The hydrocarbons are generally removed during engine
operation by drawing in clean air in the carbon canister to release
the hydrocarbons from the carbon element and move the hydrocarbons
to the intake of the engine.
To satisfy increasingly strict global evaporative emission
regulations, additional emphasis and development has been placed on
the quality and adsorbent properties of the carbon elements. For
instance, activated carbon honeycomb structures are used as bleed
elements to supplement the adsorption capacity in addition to
carbon pellets. But these carbon honeycomb structures can be
fragile and costly. These and other issues regarding carbon
elements for a carbon canister are addressed by the teachings of
the present disclosure.
SUMMARY
This section provides a general summary of the disclosure, and is
not a comprehensive disclosure of its full scope or all of its
features.
In one form, the present disclosure is directed toward a method for
producing an active carbon filter for a carbon canister. The method
includes defining a body having a honeycomb structure with a
plurality of bleed passages from a polymer based material, and
forming an adsorption layer along a surface of the body, where the
adsorption layer is made of a carbon based material.
In another form, the defining the body further includes forming a
plurality of substrates, where each of the substrates defines a
plurality of channels extending along a first axis, and stacking
the plurality of substrates along a second axis perpendicular to
the first axis to define the body having the honeycomb structure.
The adsorption layer is formed along the surface of each of the
substrates.
In yet another form, the adsorption layer is formed on each surface
of the substrates before the substrates are stacked.
In one form, the method further includes housing the body defined
by the substrates and having the adsorption layer in a case. The
case has a polymer based core with a supplemental adsorption layer
disposed along the surface of the core.
In another form, the substrates are formed using injection
molding.
In yet another form, the forming the adsorption layer further
includes, for each of the substrates, depositing the carbon based
material along the surface of the substrate. The substrates are
stacked after the adsorption layer is formed on the substrates.
In one form, the defining the body further includes injection
molding the body as a single piece using the polymer based
material.
In another form, the defining the body further includes injection
molding the body using a first material made of the polymer based
material and a second material made of the carbon based material,
and the forming the adsorption layer further includes sintering the
body made of the first and second materials to expose the carbon
based material along the surface of the body.
In yet another form, the adsorption layer is formed using one of
the following procedures: dip-coating, seeding and in situ growth,
or plasma coating.
In one form, the thickness of the adsorption layer is between 10
.mu.m to 100 .mu.m.
In one form, the present disclosure is directed toward an active
carbon filter that includes a body and an adsorption layer. The
body defines a honeycomb structure with a plurality of bleed
passages, and the body is defined by a polymer based material. The
adsorption layer is disposed along a surface of the body, and the
adsorption layer is defined by a carbon based material.
In another form, the body is defined by a plurality of substrates,
each of the substrates defines a plurality of channels extending
along a first axis, and the substrates are arranged in a stacked
configuration along a second axis perpendicular to the first axis
to defining the body having the honeycomb structure. The adsorption
layer is disposed along the surface of each of the substrates.
In yet another form, the active carbon filter further includes a
case housing the body, and the case has a core defined by the
polymer based material and a supplemental adsorption layer defined
by the carbon based material and disposed along a surface of the
core.
In one form, the present disclosure is directed toward a carbon
canister that includes one or more of the active carbon filters of
the present disclosure.
In one form, the present disclosure is directed toward a method for
producing an active carbon filter for a carbon canister. The method
includes defining a body having a honeycomb structure with a
plurality of bleed passages extending along a first axis, and
forming an adsorption layer along an entire surface of the body.
The body is formed from a polymer based material, and the
adsorption layer is made of a carbon based material.
In another form, the defining the body further includes forming a
plurality of substrates, where each of the substrates defines a
plurality of channels extending along a first axis, and stacking
the plurality of substrates along a second axis perpendicular to
the first axis to define the body having the honeycomb
structure.
In yet another form, the adsorption layer is formed on each surface
of the substrates before the substrates are stacked.
In one form, the substrates are formed using injection molding.
In another form, the forming the adsorption layer further
comprises, for each of the substrates, depositing the carbon based
material along the surface of the substrate, where the substrates
are stacked after the adsorption layer is formed on the
substrates.
In yet another form, the defining the body further comprises
injection molding the polymer based material to form the body as a
monolithic piece.
Further areas of applicability will become apparent from the
description provided herein. It should be understood that the
description and specific examples are intended for purposes of
illustration only and are not intended to limit the scope of the
present disclosure.
DRAWINGS
In order that the disclosure may be well understood, there will now
be described various forms thereof, given by way of example,
reference being made to the accompanying drawings, in which:
FIG. 1 illustrates a carbon canister having a carbon filter in
accordance with the teachings of the present disclosure;
FIGS. 2A and 2B are perspective views of the carbon filter in
accordance with the teachings of the present disclosure;
FIG. 3 is an enlarged cross-sectional view of area I of the carbon
filter in FIG. 2A;
FIG. 4 is an enlarged cross-sectional view of area II of a case of
the carbon filter in FIG. 2A;
FIG. 5 is a perspective view of a carbon filter having a plurality
of substrates in accordance with the teachings of the present
disclosure;
FIG. 6 is a partial exploded view of the carbon filter of FIG.
5;
FIG. 7 is a partial cross-sectional view of a substrate 204 in
accordance with the teachings of the present disclosure; and
FIG. 8 is a flowchart of an example routine for forming the carbon
filter in accordance with the teachings of the present
disclosure.
The drawings described herein are for illustration purposes only
and are not intended to limit the scope of the present disclosure
in any way.
DETAILED DESCRIPTION
The following description is merely exemplary in nature and is not
intended to limit the present disclosure, application, or uses. It
should be understood that throughout the drawings, corresponding
reference numerals indicate like or corresponding parts and
features.
Referring to FIG. 1, an activated carbon canister 100 is generally
included as part of an evaporative emission control system of a
vehicle to capture hydrocarbon vapor emissions from a fuel tank. In
addition to other components, the canister 100 includes a housing
102 and active carbon elements in the form of carbon pellets (not
shown) and one or more active carbon filters 104 that are arranged
within the housing 102. Hydrocarbon vapors from the fuel tank are
drawn to the surface of the activate carbon elements and stored
therein.
Referring to FIGS. 2A, 2B, 3, and 4, considering the hydrocarbons
are retained at and/or within the surface of carbon element, the
carbon filter 104 of the present disclosure is configured to have a
support structure with a layer of active carbon material deposited
thereon, where the structure and the layer are formed of different
material. In one form, the carbon filter 104 has a body 106 and an
adsorption layer 108 disposed along the surface of the body 106 to
form a bleed element for adsorbing hydrocarbons. In FIG. 3, the
body 106 and the adsorption layer 108 are shaded differently to
indicate different materials. The body 106 defines a plurality of
passages 110 that extend a long a first axis (i.e., "A" in figure)
and configured in a honeycomb structure. The body 106 is formed of
a polymer based material, such as polypropylene (PP),
polyoxymethylene (POM), polyphthalamide (PPA) and polyamide (PA).
In one form, the body 106 has a cube-like shape with a square shape
cross-section, and the thickness of the walls can be between 3.0 mm
to 0.635 mm. But, as the support structure, the shape of the body
106 may be configured in various suitable ways, and should not be
limited to the shape depicted. For example, the body 106 may be
cylindrical, a column with a square or rectangular cross-section, a
prism, or other suitable configuration.
The adsorption layer 108 extends throughout the body 106 including
through the passages 110, and is formed of a carbon based material,
such as activated carbon and carbon black. That is, the adsorption
layer 108 covers each surface of the body 106 to increase
adsorption surface area for the hydrocarbons. In one form, the
thickness of the adsorption layer 108 is between 10 .mu.m and 100
.mu.m, but other suitable thicknesses are also within the scope of
the present disclosure.
The carbon filter 104 may also include a case 112 for housing the
body 106 having the adsorption layer 108. To further decrease
hydrocarbon emissions, the case 112 is configured to have
adsorption properties. That is, in one form, the case 112 has a
core 114 formed of a polymer based material, similar to the body
106, and a supplemental adsorption layer 116 disposed along the
surface of the core and formed of a carbon based material, similar
to the adsorption layer 108 (see FIG. 4).
By separating the support structure of the carbon filter 104 from
the adsorption element, various manufacturing methods may be
employed to form the carbon filter 104. For example, in one form,
the body 106 is formed using an injection molding process and the
adsorption layer 108 is formed by coating or, in other words,
depositing the carbon material on the body 106. To form the body
106, a polymer based material that is substantially in a liquid
state is injected into a mold that has the honeycomb structure with
the plurality of passages 110. The body 106 may then undergo one or
more finishing operation to, for example, remove residual material
before the adsorption layer 108 is formed.
There are a number of coating applications that can be used to form
the adsorption layer, and are generally provided in a two-step
process in which the carbon based material is applied in the first
step and a heat treatment is performed for the second step. The
heat treatment improves the bond or adhesion between the active
particulates (i.e., carbon based material of the adsorption layer)
and the surface of the body, through either a sintering process or
in situ growth of the porous carbon based material. But the heat
treatment process is not required, and other steps may be taken to
improve the bond.
The first step may be accomplished through, for example, plasma
enhanced chemical vapor deposition, slurry-coating, in situ growth
or seeding. Plasma-enhanced chemical vapor deposition (PECVD) is an
improved form of chemical vapor deposition (CVD), and can be done
on the surface of the body 106. For example, in CVD, the object to
be coated is heated to high temperatures before the monomer is
introduced into the plasma chamber. In PECVD, on the other hand,
plasma is used to accelerate the coating process. The adsorption
capacity of the surface may be achieved by tailoring the surface
chemical properties, and porosity. By plasma coating, highly
cross-linked hydrocarbon layers can be deposited on the body 106,
and these layers may have diamond-like properties by being
extremely hard, smooth, and chemically resistant.
The slurry-coating may contain particles of nickel, silver, copper,
or graphite, in either an acrylic or urethane resin. These coatings
are available with solid contents of about 30 to 60 percent, by
volume. Typically, an effective dry film thickness ranges from 1 to
5 mils (1 mil=25.4 micron).
In one form, for seeding and in situ growth, the body 106 is:
impregnated with a gel or synthesis solution, followed by a flow
coating or dip coating procedure, then evaporation induced
self-assembly followed by a hydrothermal treatment to trigger in
situ growth. These methods improve adhesion between the porous
coating (i.e., the adsorption layer 108) and the body 106.
The adsorption layer may also be formed by a dip-coating process
that improves control of the thickness of the adsorption layer by
controlling the number of coatings. To improve adhesion between the
surface of the body 106 and the coats, Aminopropyltriethoxysilane
(APTS) is used together with surfactant Triton X-100.
While specific examples for forming the adsorption layer 108 is
provided, other suitable methods may be used while remaining within
the scope of the present disclosure.
In another form, the carbon filter 104 may be formed by a
two-material injection molding process in which a composite
material formed by a mixture of the polymer and carbon based
materials is used as the feed material for an injection molding
process. The molding process forms the body 106 having the
honeycomb shape. To form the adsorption layer 108, the body 106
undergoes a sintering process to remove the polymer based material
from the surface leaving the carbon based material as the
adsorption layer.
Using the methods described herein, the body 106 of the carbon
filter 104 may be formed from a one piece monolithic structure
having the plurality of passages 110 and honeycomb structure. In
another form, the body 106 may be defined by a plurality of
substrates that are arranged in a stacked configuration to form the
honeycomb structure. More particularly, referring to FIGS. 5 to 7,
a carbon filter 200 has a body 202 defined by a plurality of
substrates 204 (e.g., substrates 204.sub.1, 204.sub.2, 204.sub.3, .
. . , 204.sub.N), where each substrate 204 defines a plurality of
channels 206 extending along the first axis. Each of the substrates
204 has a core portion 208 formed of a polymer based material, and
an adsorption layer 210 disposed along the surface of the core
portion 208 (FIG. 7).
By having the body 202 defined by the plurality of substrates 204,
each substrate 204 may be formed using the methods described herein
and then arranged in the stacked configuration. For example, in one
form, the core portions 208 of the substrates 204 are formed by the
injection molding process using a polymer based material, and then
the carbon based material is deposited on the surface of the core
to form the adsorption layer 210.
In another example, using a two-step injection molding process, the
core portion 208 of each of the substrate 204 is molded using the
polymer based material as the feeding material. Next, the
adsorption layer 210 is molded or deposited on the top of the core
portion 208 using the carbon-based material as the feeding
material. Due to the heat of the two materials, the adsorption
layer 210 is bonded or adheres to the core portion 208.
The plurality of substrates 204 are stacked along a second axis
(i.e., axis B in figure) that is perpendicular to the first axis,
and are retained in position by way of a fastening mechanism. In
one form, the fastening mechanism is provided as snap fastener 214s
provided between a pair of adjacent substrates 204, such as
substrates 2041 and 2042. Each of the snap fasteners 214 includes
an arm member 216 and an annular member 218 that receives the arm
member 216. The arm member 216 is arranged on one of the substrates
2041 and the annular member 218 is disposed on the other substrate
2042, such that when stacked together, the arm member 216 is
inserted and snaps in the annual member 218. Once stacked the
substrates 204 define the body 106 having the adsorption, the
substrates 204 may be arranged in a case.
As illustrated, the snap fasteners 214 are formed along two
opposite corners of the substrates 204, but may be arranged at
other positions along the substrates 204, such as along the side of
the substrates 204. In addition, any number of snap fasteners 214
may be used and should not be limited to two per pair of substrates
204. Furthermore, other forms of fastening the substrates 204 to
form the body 202 may also be used (e.g. adhesive), and should not
be limited to the mechanical fasteners like the snap fastener
illustrated.
Referring to FIG. 8, an example routine 300 for forming a carbon
filter of the present disclosure is provided. At 302, a body having
a honeycomb structure with a plurality of passages is defined using
an injection molding process with a polymer based material. At 304,
an adsorption layer is formed along a surface of the body with a
carbon based material. The adsorption layer may be formed using any
of the processes described above.
The carbon filter of the present disclosure is defined by two
different materials, where one material is selected to form the
support structure of the filter and the other is for forming the
adsorption layer to capture hydrocarbons. Accordingly, the strength
of the carbon filter is improved, and the cost of the filter can be
controlled based on the materials selected. In addition, the method
of producing the filter improves packaging space and increases
flexibility in designing the shape/configuration of the filter.
The description of the disclosure is merely exemplary in nature
and, thus, variations that do not depart from the substance of the
disclosure are intended to be within the scope of the disclosure.
Such variations are not to be regarded as a departure from the
spirit and scope of the disclosure.
* * * * *