Ceramic processing firing

Patent metadata

Field	Value
Publication number	US-9221192-B2
Application number	US-201213885271-A
Country	US
Kind code	B2
Filing date	Jan 6, 2012
Priority date	Nov 30, 2010
Publication date	Dec 29, 2015
Grant date	Dec 29, 2015

Abstract

A process for producing a honeycomb ceramic article includes providing a green honeycomb body including ceramic-forming materials and organic pore forming materials and subjecting the green honeycomb body to a firing cycle in a kiln in which steam is added to the kiln atmosphere in an amount from about 10% to about 100%, based on volume. Also provided are ceramic articles produced by the process.

First claim

What is claimed is:

1. A process for producing a honeycomb ceramic article, the process comprising:
providing a green honeycomb body including inorganic ceramic-forming materials and organic pore forming materials; and
subjecting the green honeycomb body to a firing cycle in a kiln in which steam is added to the kiln atmosphere in an amount from about 40% to about 100%, based on volume.

2. The process of claim 1 , wherein the addition of steam to the kiln atmosphere occurs at least during a portion of the firing cycle below about 1000° C.

3. The process of claim 1 , wherein the inorganic ceramic-forming materials yield at least one of cordierite, mullite, aluminum-titanate, silicon carbide, or alumina when subjected to the firing cycle.

4. The process of claim 2 , wherein the addition of steam to the kiln atmosphere occurs during a top soak portion of the firing cycle.

5. The process of claim 1 , wherein the steam is mixed with air, oxygen, nitrogen or mixtures thereof.

6. The process of claim 1 , wherein a kiln temperature is increased from room temperature to at least about 800° C. at a rate of from about 50° C/hr to about 100° C/hr.

7. The process of claim 1 , wherein a kiln temperature is decreased from a top soak temperature during the firing cycle at a rate of greater than about 50°C./hour.

8. The process of claim 7 , wherein the kiln temperature is decreased from a top soak temperature during the firing cycle at a rate of greater than about 100°C./hour.

9. The process of claim 1 , wherein the firing cycle is less than about 100 hours long.

10. The process of claim 1 , wherein the firing cycle is less than about 65 hours long.

11. The process of claim 1 , wherein the organic pore forming materials comprise greater than about 20 weight percent by super addition.

12. The process of claim 1 , wherein the organic pore forming materials comprise at least one of graphite and starch.

13. A ceramic article produced by:
providing inorganic ceramic-forming ingredients, a cellulose based binder, an aqueous based solvent and a pore forming agent;
mixing the ceramic-forming ingredients, the binder, the solvent, and the pore forming agent to form a precursor batch, the precursor batch comprising organic materials in an amount greater than about 30 wt. % by super addition;
forming the precursor batch into a green honeycomb body; and
firing the green honeycomb body to produce the ceramic article, wherein steam is added to a firing atmosphere in an amount from about 40% to about 100%, based on volume at least during a portion of the firing cycle below about 1000° C., wherein
the inorganic ceramic-forming ingredients yield cordierite, and
the ratio of orthorhombic cordierite to hexagonal cordierite is greater than about 9 to 1.

14. The ceramic article of claim 13 , wherein firing comprises decreasing the temperature from a top soak temperature during the firing cycle at a rate of greater than about 100° C./hour.

15. The ceramic article of claim 13 , wherein the ceramic article is a honeycomb monolith.

16. The ceramic article of claim 13 , wherein the pore forming agent is at least one of graphite and starch.

17. The ceramic article of claim 13 , wherein the steam is present from about 40% to about 60% by volume.

18. The ceramic article of claim 13 , wherein the firing cycle is less than about 65 hours long.

19. A process for producing a honeycomb ceramic article, the process comprising:
providing a green honeycomb body including inorganic ceramic-forming materials and organic pore forming materials; and
subjecting the green honeycomb body to a firing cycle in a kiln in which steam is added to the kiln atmosphere in an amount from about 10% to about 100%, based on volume,
wherein the inorganic ceramic-forming materials yield at least one of cordierite, mullite, aluminum-titanate, or alumina when subjected to the firing cycle.

Assignees

• Beall Douglas Munroe
• Bookbinder Dana Craig
• Wang Jianguo
• Corning Inc

Inventors

• Beall Douglas Munroe
• Bookbinder Dana Craig
• Wang Jianguo

Classifications

• C04B2235/6565

  Cooling rate · CPC title

• C04B38/0006

  Honeycomb structures (from one or more corrugated sheets by winding or stacking C04B38/0083) · CPC title

• C04B38/068

  Carbonaceous materials, e.g. coal, carbon, graphite, hydrocarbons · CPC title

• C04B2235/76

  Crystal structural characteristics, e.g. symmetry · CPC title

• C04B35/478

  based on aluminium titanates · CPC title