Particulate filters

Patent metadata

Field	Value
Publication number	US-11207667-B2
Application number	US-202016947719-A
Country	US
Kind code	B2
Filing date	Aug 13, 2020
Priority date	Aug 15, 2019
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

A vehicular exhaust filter (2) comprising a porous substrate having an inlet face and an outlet face with the porous substrate comprising inlet channels extending from the inlet face and outlet channels extending from the outlet face is disclosed. The inlet channels and the outlet channels are separated by a plurality of filter walls having a porous structure.The vehicular exhaust filter (2) is loaded with a refractory powder having a tapped density before loading of less than 0.10 g/cm3 and the vehicular exhaust filter has a mass loading of the refractory powder of less than 10 g/l.

First claim

The invention claimed is:

1. A vehicular exhaust filter comprising a porous substrate having an inlet face and an outlet face, the porous substrate comprising inlet channels extending from the inlet face and outlet channels extending from the outlet face; the inlet channels and the outlet channels being separated by a plurality of filter walls having a porous structure;
the vehicular exhaust filter being loaded with a refractory powder having a tapped density before loading of less than 0.10 g/cm 3 ;
the vehicular exhaust filter having a mass loading of the refractory powder of less than 10 g/l; and
wherein greater than 40% of the refractory powder is located within the porous structure of the plurality of filter walls and less than 60% of the refractory powder is coated on an external surface of the plurality of filter walls.

2. The vehicular exhaust filter of claim 1 , wherein greater than 50% of the refractory powder, optionally greater than 65% of the refractory powder, optionally greater than 75% of the refractory powder, optionally up to 100% of the refractory powder is located within the porous structure of the plurality of filter walls.

3. The vehicular exhaust filter of claim 1 , wherein the percentage of the refractory powder located within the porous structure of the plurality of filter walls is calculated by the formula:

%
⁢

⁢

Powder
inwall

=

(

1
-

(

[

Envelope
⁢

⁢

volume

powdercoated
⁢

⁡

(
ml
)

-

Envelope
⁢

⁢

volume

bare
⁢

⁡

(
ml
)

]

·
Bulk

⁢

⁢
density
⁢

⁢

(

g
·

ml

-
1

)

Powder
⁢

⁢
loading
⁢

⁢
of
⁢

⁢
filter
⁢

⁢

(
g
)

)

)

·
100

⁢

%
.

4. The vehicular exhaust filter of claim 1 , wherein the refractory powder has a tapped density before loading of less than 0.08 g/cm 3 , optionally less than 0.07 g/cm 3 , optionally less than 0.06 g/cm 3 , optionally less than 0.05 g/cm 3 .

5. The vehicular exhaust filter of claim 1 , wherein the mass loading of the refractory powder is less than 7 g/l, optionally less than 5 g/l, optionally less than 3 g/l, optionally less than 1 g/l.

6. The vehicular exhaust filter of claim 1

Assignees

• Johnson Matthey Plc

Inventors

• Bellham Peter
• Chiffey Andrew
• Clowes Lucy
• Hotchkiss Thomas
• Marvell David
• Turner John
• Warren Sarah

Classifications

• B01D53/9445 Primary

  Simultaneously removing carbon monoxide, hydrocarbons or nitrogen oxides making use of three-way catalysts [TWC] or four-way-catalysts [FWC] · CPC title

• B01D2279/30

  for treatment of exhaust gases from IC Engines · CPC title

• B01D2267/30

  Same type of filters · CPC title

• B01D2255/1021

  Platinum · CPC title

• F01N2510/00

  Surface coverings · CPC title