Fugitive Pore Former For Porous Ceramic Articles

• US 20090057939A1
• Filed: 03/31/2008
• Published: 03/05/2009
• Est. Priority Date: 08/28/2007
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Brocheton, Yves A.H., Henry, David
• Granted Patent: US 7,914,874 B2
• Time in Patent Office: Days
• US Class Current: 264/43
• CPC Class Codes: C04B 2111/00793 as filters or diaphragms
• CPC Class Codes: C04B 2111/0081 as catalysts or catalyst carriers
• CPC Class Codes: C04B 35/185 Mullite 3Al2O3-2SiO2
• CPC Class Codes: C04B 35/195 Alkaline earth aluminosilicates, e.g. cordierite or anorthite
• CPC Class Codes: C04B 35/478 based on aluminium titanates
• CPC Class Codes: C04B 35/565 based on silicon carbide
• CPC Class Codes: C04B 38/0006 Honeycomb structures from one or more corrugated sheets by winding or stacking C04B38/0083
• CPC Class Codes: C04B 38/0054 the pores being microsized or nanosized
• CPC Class Codes: C04B 38/0074 expressed as porosity percentage
• CPC Class Codes: C04B 38/0605 by sublimating
• CPC Class Codes: Y10T 428/24149 Honeycomb-like
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

Disclosed are ceramic batch compositions for forming porous ceramic articles. The ceramic forming precursor batch compositions include ceramic forming inorganic batch components and a cyclododecane pore forming agent. Also disclosed are methods for manufacturing porous ceramic articles.

Claims

1. A plasticized ceramic precursor batch composition comprising:

ceramic forming inorganic batch components; and

a pore forming agent comprising cyclododecane.

2. The plasticized ceramic precursor batch composition of claim 1, wherein the ceramic forming inorganic batch components are selected to provide a sintered phase cordierite composition.

3. The plasticized ceramic precursor batch composition of claim 2, wherein the sintered phase cordierite composition is characterized on an oxide weight basis as consisting essentially of:

about 49 to about 53 percent by weight SiO₂,

about 33 to about 38 percent by weight Al₂O₃, and

about 12 to about 16 percent by weight MgO.

4. The plasticized ceramic precursor batch composition of claim 1, wherein the ceramic forming inorganic batch components are selected to provide a sintered phase mullite composition.

5. The plasticized ceramic precursor batch composition of claim 1, wherein the ceramic forming inorganic batch components are selected to provide a sintered phase aluminum titanate composition.

6. The plasticized ceramic precursor batch composition of claim 1, wherein the ceramic forming inorganic batch components are selected to provide a sintered phase silicon carbide composition.

7. The plasticized ceramic precursor batch composition of claim 1, wherein the cyclododecane has a median particle size d₅₀ of from about 90 μ

m to about 110 μ

m.

8. The plasticized ceramic precursor batch composition of claim 1, wherein the cyclododecane is present as substantially spherical particles.

9. The plasticized ceramic precursor batch composition of claim 1, wherein the batch composition is formed into a predetermined shape.

10. The plasticized ceramic precursor batch composition of claim 9, wherein the predetermined shape is a honeycomb structure.

11. The plasticized ceramic precursor batch composition of claim 1, further comprising a liquid vehicle and an organic binder system.

12. A method for manufacturing a porous ceramic honeycomb article, comprising the steps of:

providing a plasticized ceramic forming precursor batch composition of claim 1, comprising;

ceramic forming inorganic batch components; and

a pore forming agent comprising cyclododecane;

forming a honeycomb green body from the plasticized ceramic forming precursor batch composition, and

firing the honeycomb green body under conditions effective to convert the green body into a porous ceramic honeycomb article.

13. The method of claim 12, wherein the plasticized ceramic forming precursor batch composition comprises ceramic forming inorganic batch components selected to provide at least one of a sintered phase cordierite composition, sintered phased mullite composition, a sintered phase aluminum titanate composition, or combinations thereof.

14. The method of claim 13, wherein the ceramic forming inorganic batch components are selected to provide a sintered phase cordierite composition, as characterized on an oxide weight basis, consisting essentially of:

about 49 to about 53 percent by weight SiO₂;

about 33 to about 38 percent by weight Al₂O₃; and

about 12 to about 16 percent by weight MgO.

15. The method of claim 12, wherein the cyclododecane pore former is present in the plasticized ceramic forming precursor batch composition having a predetermined size and shape.

16. The method of claim 15, wherein the cyclododecane pore former is present in the plasticized ceramic forming precursor batch composition as substantially spherical particles.

17. The method of claim 16, wherein the substantially spherical cyclododecane particles have a median particle size dp₅₀ of from about 90 μ

m to about 110 μ

m.

18. The method of claim 12, wherein the step of forming the honeycomb green body comprises shaping the plasticized ceramic forming precursor batch composition into a honeycomb shape, and drying the shaped plasticized ceramic forming precursor composition under conditions effective to at least remove some of the cyclododecane pore former.

19. The method of claim 12, wherein the effective firing conditions comprise firing the honeycomb green body at a soak temperature at from about 1300°

C. to about 1450°

C., and subsequently holding the soak temperature for a period of time sufficient to convert the honeycomb green body into a ceramic honeycomb article.

20. The method of claim 19, wherein the soak temperature is achieved by increasing temperature from 1150°

C. to the soak temperature at a rate of increase greater than 100°

C. per hour.

21. The method of claim 12, wherein the plasticized ceramic forming precursor batch composition further comprises a liquid vehicle and an organic binder system.

22. A porous ceramic honeycomb article manufactured by the method of claim 12.

23. The porous ceramic honeycomb article of claim 22, having a total porosity (% P) of from about 60% to about 70%, and a median pore size (d₅₀) of from about 15 μ

m to about 25 μ

m.

25. The method of claim 12 wherein the step of forming the honeycomb green body comprises shaping and then drying the shaped plasticized ceramic forming precursor composition under conditions effective to remove substantially all of the cyclododecane pore former.

24. A green honeycomb article, comprising ceramic forming precursor materials and a cyclododecane pore former.