Evaporative fuel vapor emission control systems

Patent metadata

Field	Value
Publication number	US-2020291904-A1
Application number	US-202016888323-A
Country	US
Kind code	A1
Filing date	May 29, 2020
Priority date	Jun 19, 2017
Publication date	Sep 17, 2020
Grant date	—

Abstract

The present disclosure describes an evaporative emission control canister system that includes: one or more canisters comprising at least one vent-side particulate adsorbent volume comprising a particulate adsorbent having microscopic pores with a diameter of less than about 100 nm; macroscopic pores having a diameter of about 100-100,000 nm; and a ratio of a volume of the macroscopic pores to a volume of the microscopic pores that is greater than about 150%, and having a retentivity of about 1.0 g/dL or less. The system may further include a high butane working capacity adsorbent. The disclosure also describes a method for reducing emissions in an evaporative emission control system.

First claim

What is claimed is:

1 . An adsorbent material for evaporative emission control comprising:
a particulate activated carbon material having microscopic pores with a diameter of less than about 100 nm, macroscopic pores having a diameter of about 100-100,000 nm, and a ratio of the volume of the macroscopic pores to the volume of the microscopic pores that is greater than about 150%,
wherein the particulate activated carbon material has less than 40 Pa/cm pressure drop when a 46 cm/s apparent linear air flow velocity is applied to a 43 mm diameter bed of the particulate activated carbon material, and at least one of (i) a nominal butane working capacity (BWC) of <8 g/dL, (ii) a butane retentivity of less than about 2 g/dL or (iii) a combination of (i) and (ii).

2 . The adsorbent material of claim 1 , wherein the adsorbent has a butane retentivity of 1.0 g/dL or less.

3 . The adsorbent material of claim 1 , wherein the adsorbent has a butane retentivity of about 0.25 to 1.0 g/dL.

4 . The adsorbent material of claim 1 , wherein the adsorbent is at least one of activated carbon, carbon charcoal, molecular sieves, porous polymers, porous alumina, clay, porous silica, kaolin, zeolites, metal organic frameworks, titania, ceria, or a combination thereof.

5 . The adsorbent material of claim 1 , wherein the adsorbent has a micropore volume as determined by BJH of about 0.5 cc/g or less.

6 . The adsorbent material of claim 1 , wherein the adsorbent comprises a body defining an exterior surface and a hollow shape or morphology.

7 . The adsorbent material of claim 6 , wherein the three-dimensional low flow resistance shape or morphology is at least one of substantially a cylinder, substantially an oval prism, substantially a sphere, substantially a cube, substantially an elliptical prism, substantially a rectangular prism, a trilobe prism, a three-dimensional spiral, or a combination thereof.

8 . The adsorbent material of claim 1 , wherein the particulate adsorbent material has a cross-sectional width of about 1 mm to about 20 mm.

9 . The adsorbent material of claim 1 , wherein the adsorbent has a hollow shape in cross section.

10 . The adsorbent material of claim 1 , wherein the adsorbent includes at least one cavity in fluid communication with the exterior surface of the adsorbent.

11 . The adsorbent material of claim 1 , wherein each part of the adsorbent has a thickness of about 0.1 mm to about 3.0 mm.

12 . The adsorbent material of claim 9 , wherein at least one of:
at least one exterior wall of the hollow shape has a thickness in a range of about 0.1 mm to about 1.0 mm; the hollow shape has at least one interior wall extending between the exterior walls and having a thickness in a range of about 0.1 mm to about 1.0 mm; or a combination thereof.

13 . The adsorbent material of claim 12 , wherein the thickness of at least one of the interior wall, the exterior wall or a combination thereof is about 0.3 mm to about 0.8 mm.

14 . The adsorbent material of claim 13 , wherein the thickness of at least one of the interior wall, the exterior wall or a combination thereof is about 0.4 mm to about 0.7 mm.

15 . The adsorbent material of claim 13 , wherein the interior wall extends outward to the exterior wall in at least two directions from a hollow portion of the particulate adsorbent material.

16 . The adsorbent material of claim 13 , wherein the interior walls extends outward to the exterior wall in at least three directions from a hollow portion of the particulate adsorbent material.

17 . The adsorbent material of claim 13 , wherein the interior walls extends outward to the exterior wall in at least four directions from a hollow portion of the particulate adsorbent material.

18 . The adsorbent material of claim 1 , wherein the adsorbent has a length of about 1 mm to about 20 mm.

19 . The adsorbent material of claim 4 , wherein the activated carbon is derived from at least one material selected from the group consisting of wood, wood dust, wood flour, cotton linters, peat, coal, coconut, lignite, carbohydrates, petroleum pitch, petroleum coke, coal tar pitch, fruit pits, fruit stones, nut shells, nut pits, sawdust, palm, vegetables, synthetic polymer, natural polymer, lignocellulosic material, and combinations thereof.

20 . The adsorbent material of claim 4 , wherein the clay is at least one of Zeolite clay, Bentonite clay, Montmorillonite clay, Illite clay, French Green clay, Pascalite clay, Redmond clay, Terramin clay, Living clay, Fuller's Earth clay, Ormalite clay, Vitallite clay, Rectorite clay, or a combination thereof.

21 . The adsorbent material of claim 1 , further comprises at least one of:
a pore forming material or processing aid that decomposes, solubilizes, sublimates, vaporizes, or melts when heated to a temperature of 100° C. or more; a binder; a filler; or a combination thereof.

22 . The particulate adsorbent material of claim 21 , wherein the pore forming material or processing aid is a cellulose derivative.

23 . The particulate adsorbent material of claim 21 , wherein the pore forming material or processing aid is methylcellulose.

24 . The particulate adsorbent material of claim 21 , wherein the pore forming material or processing aid sublimates, vaporizes, chemically decomposes, solubilizes or melts when heated to a temperature in a range of about 125° C. to about 640° C.

25 . The particulate adsorbent material of claim 21 , wherein the binder is clay or a silicate material.

26 . The particulate adsorbent material of claim 25 , wherein the clay is at least one of Zeolite clay, Bentonite clay, Montmorillonite clay, Illite clay, French Green clay, Pascalite clay, Redmond clay, Terramin clay, Living clay, Fuller's Earth clay, Ormalite clay, Vitallite clay, Rectorite clay, or a combination thereof.

Assignees

• Ingevity South Carolina Llc

Inventors

• Byrne Timothy M
• Hiltzik Laurence H
• Leon Garcia Marta
• Thomson Cameron I

Classifications

• F02M25/089

  Layout of the fuel vapour installation · CPC title

• B01D53/0407 Primary

  Constructional details of adsorbing systems · CPC title

• B01D2253/104

  Alumina · CPC title

• B01D2253/108

  Zeolites · CPC title

• B01D2253/106

  Silica or silicates · CPC title