Cordierite porous ceramic honeycomb articles

Patent metadata

Field	Value
Publication number	US-9856177-B2
Application number	US-78983310-A
Country	US
Kind code	B2
Filing date	May 28, 2010
Priority date	May 28, 2010
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

Porous ceramic honeycomb articles for use as particulate filters and processes for making the same are described herein. The porous ceramic honeycomb articles include a fired cordierite body. The fired cordierite body has a microcrack parameter (Nb 3 ) of about 0.05 to about 0.25 prior to exposure to a microcracking condition. After exposure to the microcracking condition, the fired cordierite body has a microcrack parameter (Nb 3 ) at least 20% greater than the microcrack parameter prior to exposure to the microcracking condition. The fired cordierite body has a coefficient of thermal expansion (CTE) of about 7.0×10 −7 /° C. to about 15.0×10 −7 /° C. over from about 25° C. to about 800° C. prior to exposure to the microcracking condition and a coefficient of thermal expansion of about 1.0×10 −7 /° C. to about 10.0×10 −7 /° C. over from about 25° C. to about 800° C. after exposure to the microcracking condition. The microcrack parameter may include a thermal cycle or a chemical treatment.

First claim

What is claimed is:

1. A porous ceramic honeycomb article, comprising:
a fired cordierite body having an as-fired microcrack parameter (Nb 3 ) of from 0.08 to about 0.25, wherein, when the fired cordierite body is exposed to an acid wash, the fired cordierite body comprises an acid wash-induced microcrack parameter (Nb 3 ) that is at least 20% greater than the as-fired microcrack parameter.

2. The porous ceramic honeycomb article of claim 1 , wherein the fired cordierite body further comprises an as-fired coefficient of thermal expansion (CTE) of from about 7.0×10 −7 /° C. to about 15.0×10 −7 /° C. over from about 25° C. to about 800° C., and an acid wash-induced coefficient of thermal expansion of from about 1.0×10 −7 /° C. to about 10.0×10 −7 /° C. over from about 25° C. to about 800° C.

3. The porous ceramic honeycomb article of claim 1 , wherein the fired cordierite body further comprises an as-fired and an acid wash-induced surface porosity of from about 38% to about 45%.

4. The porous ceramic honeycomb article of claim 1 , wherein the fired cordierite body is manufactured from a batch of inorganic components including talc having d pt50 ≦10 μm, a silica-forming source having d ps50 ≦20 μm, an alumina-forming source having a median particle diameter d pa50 of less than or equal to 10.0 μm, and a pore former having d pp50 ≦20 μm, wherein d pp50 is a median particle diameter of the pore former, d ps50 is a median particle diameter of the silica-forming source, d pa50 is a median particle diameter of the alumina-forming source, and d pt50 is a median particle diameter of the talc.

5. A porous ceramic honeycomb article, comprising:
a fired cordierite body having an as-fired microcrack parameter (Nb 3 ) of from 0.08 to about 0.25, an as-fired coefficient of thermal expansion (CTE) of from about 7.0×10 −7 /° C. to about 15.0×10 −7 /° C. over from about 25° C. to about 800° C., an as-fired d f of less than or equal to about 0.3, wherein d f =(d 50 −d 10 )/d 50 , an as-fired d b of less than or equal to about 1.5, wherein d b =(d 90 −d 10 )/d 50 ,
wherein, when the fired cordierite body is exposed to an acid wash, the fired cordierite body comprises an acid wash-induced microcrack parameter (Nb 3 ) that is at least 20% greater than the as-fired microcrack parameter, an acid wash-induced coefficient of thermal expansion (CTE) of from about 1.0×10 −7 /° C. to about 10.0×10 −7 /° C. over from about 25° C. to about 800° C., an acid wash-induced d f of less than or equal to about 0.3, and an acid wash-induced d b of less than or equal to about 1.5, wherein d b =(d 90 −d 10 )/d 50 .

6. The porous ceramic honeycomb article of claim 5 , wherein the fired cordierite body further comprises an as-fired and an acid wash-induced d f of less than or equal to about 0.2.

7. The porous ceramic honeycomb article of claim 5 , wherein the fired cordierite body further comprises an as-fired and an acid wash-induced surface porosity of from about 38% to about 45%.

8. The porous ceramic honeycomb article of claim 5 , wherein the fired cordierite body further comprises an as-fired and an acid wash-induced total porosity (% P) of from about 50% to about 70%.

9. The porous ceramic honeycomb article of claim 5 , wherein the fired cordierite body further comprises an as-fired and an acid wash-induced surface porosity/total porosity ratio of greater than about 0.5.

10. The porous ceramic honeycomb article of claim 5 , wherein the fired cordierite body further comprises an as-fired and an acid wash-induced mean pore size (d 50 ) of from about 7 μm to about 16 μm.

11. The porous ceramic honeycomb article of claim 5 , wherein the fired cordierite body further comprises an acid wash-induced thermal shock limit of greater than 1000° C.

12. The porous ceramic honeycomb article of claim 5 , wherein the fired cordierite body has a 200/10 geometry and further comprises an as-fired modulus of rupture strength (MOR) of greater than about 300 psi, and an acid wash-induced modulus of rupture strength of greater than about 200 psi.

13. The porous ceramic honeycomb article of claim 5 , wherein the fired cordierite body has a 200/10 geometry and further comprises an as-fired elastic modulus (E mod ) of greater than about 3.0×10 5 psi, and an acid wash-induced elastic modulus of greater than about 2.0×10 5 psi.

14. The porous ceramic honeycomb article of claim 5 , wherein the fired cordierite body is manufactured from a batch of inorganic components including talc having d pt50 ≦10 μm, a silica-forming source having d ps50 ≦20 μm, an alumina-forming source having a median particle diameter d pa50 of less than or equal to 10.0 μm, and a pore former having d pp50 ≦20 μm, wherein d pp50 is a median particle diameter of the pore former, d ps50 is a median particle diameter of the silica-forming source, d pa50 is a median particle diameter of the alumina-forming source, and d pt50 is a median particle diameter of the talc.

15. A porous ceramic honeycomb article, comprising:
a fired cordierite body having an as-fired microcrack parameter (Nb 3 ) of from 0.08 to about 0.25, an as-fired coefficient of thermal expansion (CTE) of from about 7.0×10 −7 /° C. to about 15.0×10 −7 /° C. over from about 25° C. to about 800° C., an as-fired surface porosity of from about 38% to about 45%,
wherein, when the fired cordierite body is exposed to an acid wash, the fired cordierite body comprises an acid wash-induced microcrack parameter (Nb 3 ) that is at least 20% greater than the as-fired microcrack parameter, an acid wash-induced coefficient of thermal expansion (CTE) of from about 1.0×10 −7 /° C. to about 10.0×10 −7 /° C. over from about 25° C. to about 800° C., and an acid wash-induced surface porosity of from about 38% to about 45%, wherein
the fired cordierite body further comprises an as-fired and an acid wash-induced d f of less than or equal to about 0.3, wherein d f =(d 50 −d 10 )/d 50 , and
the fired cordierite body further comprises an as-fired and an acid wash-induced d b of less than or equal to about 1.5, wherein d b =(d 90 −d 10 )/d 50 .

16. The porous ceramic honeycomb article of claim 1 , wherein the fired cordierite body further comprises an as-fired and an acid wash-induced d b of less than or equal to about 1.2.

17. The porous ceramic honeycomb article of claim 5 , wherein the fired cordierite body further comprises an as-fired and an acid wash-induced d b of less than or equal to about 1.2.

18. The porous ceramic honeycomb article of claim 15 , wherein the fired cordierite body further comprises an as-fired and an acid wash-induced d b of less than or equal to about 1.2.

19. The porous ceramic honeycomb article of claim 1 , wherein
the fired cordierite body further comprises an as-fired and an acid wash-induced d f of less than or equal to about 0.3, wherein d f =(d 50 −d 10 )/d 50 , and
the fired cordierite body further comprises an as-fired and an acid wash-induced d b of less than or equal to about 1.5, wherein d b =(d 90 −d 10 )/d 50 .

Assignees

• Miao Weiguo
• Wang Jianguo
• Corning Inc

Inventors

• Miao Weiguo
• Wang Jianguo

Classifications

• F01N3/0222

  the structure being monolithic, e.g. honeycombs · CPC title

• B01D46/2425

  characterized by parameters related to the physical properties of the honeycomb structure material · CPC title

• B01D2046/2433

  Operations & Transport · mapped topic

• C04B38/0074

  expressed as porosity percentage · CPC title

• Y10T428/24149

  Honeycomb-like · CPC title