Aluminum titanate ceramic forming batch mixtures and green bodies with pore former

• US 20080300127A1
• Filed: 05/30/2008
• Published: 12/04/2008
• Est. Priority Date: 05/31/2007
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Tennent, David Lambie, Warren, Christopher John
• Granted Patent: US 7,977,266 B2
• Time in Patent Office: Days
• US Class Current: 501/80
• 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 2111/10 Compositions or ingredients thereof characterised by the absence or the very low content of a specific material
• CPC Class Codes: C04B 2235/3208 Calcium oxide or oxide-forming salts thereof, e.g. lime
• CPC Class Codes: C04B 2235/3213 Strontium oxides or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3218 Aluminium (oxy)hydroxides, e.g. boehmite, gibbsite, alumina sol
• CPC Class Codes: C04B 2235/3227 Lanthanum oxide or oxide-forming salts thereof
• CPC Class Codes: C04B 2235/3418 Silicon oxide, silicic acids or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint
• CPC Class Codes: C04B 2235/77 Density
• CPC Class Codes: C04B 35/478 based on aluminium titanates
• CPC Class Codes: C04B 35/6263 characterised by their solids loadings, i.e. the percentage of solids
• 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 38/0645 Burnable, meltable, sublimable materials
• CPC Class Codes: C04B 38/068 Carbonaceous materials, e.g. coal, carbon, graphite, hydrocarbons

Abstract

A ceramic forming batch mixture including inorganic batch materials, such as sources of alumina, titania, and silica, a low amount of one or more pore formers including at least one starch; an organic binder; and a solvent. Also disclosed is a method for producing a ceramic article involving mixing the inorganic batch materials with the low amount of pore former, adding an organic binder and a solvent, forming a green body; and firing the green body. A green body having a low amount of the one or more pore formers including starch is disclosed.

Claims

1. A method of manufacturing an aluminum titanate containing ceramic article, comprising the steps of:

mixing inorganic batch materials with a pore former to form a batch composition, wherein the pore former is in less than 15%, by weight, of the inorganic batch material;

adding an organic binder and a solvent to the batch composition and further mixing to form a plasticized mixture;

forming a green body from the plasticized mixture; and

firing the green body to produce a predominant phase of aluminum titanate.

2. A method of manufacturing an aluminum titanate containing ceramic article, comprising the steps of:

mixing inorganic batch materials with a pore former to form a batch composition, wherein the pore former comprises graphite in less than 10%, by weight, of the inorganic batch material and wherein the pore former comprises no thermoplastic polymer;

adding an organic binder and a solvent to the batch composition and further mixing to form a plasticized mixture;

forming a green body from the plasticized mixture; and

firing the green body to produce a fired ceramic article with a predominant phase of aluminum titanate, wherein the fired ceramic article has a porosity greater than 40%.

3. The method of claim 2 wherein the fired ceramic article has a porosity greater than 40% and less than 50%.

4. The method of claim 2 wherein the pore former comprises graphite in less than 8%, by weight, of the inorganic batch material.

5. The method of claim 2 wherein the fired ceramic article has a median pore size less than 15.0 μ

m.

6. The method of claim 2 wherein the fired ceramic article has a pore size distribution with (d₅₀−

d₁₀)/d₅₀ of less than 0.7.

7. An aluminum titanate ceramic forming batch mixture, comprising:

inorganic batch materials comprising sources of alumina, titania, and silica;

a pore former comprising a starch, wherein the pore former is in less than 15%, by weight, of the inorganic batch material;

an organic binder; and

a solvent.

8. The batch mixture of claim 7 wherein the pore former consists of the starch and graphite.

9. The batch mixture of claim 7 wherein the starch is selected from a group consisting of corn starch, barley starch, bean starch, potato starch, rice starch, tapioca starch, pea starch, sago palm starch, wheat starch, canna starch, and combinations thereof.

10. The batch mixture of claim 7 wherein the starch constitutes no less than 1% and no more than 8%, by weight, of the inorganic batch materials.

11. The batch mixture of claim 7 wherein the pore former further comprises graphite.

12. The batch mixture of claim 11 wherein the graphite is in no more than 8%, by weight, of the inorganic batch materials.

13. The batch mixture of claim 11 wherein the starch is in no more than 8%, by weight, of the inorganic batch materials, and the graphite is in no more than 8%, by weight, of the inorganic batch materials.

14. The batch mixture of claim 7 wherein the pore former comprises no thermoplastic polymer.

15. The batch mixture of claim 7 wherein the inorganic batch materials contains more than 1% and less than 8%, by weight, of the pore former.

16. The batch mixture of claim 7 wherein the pore former comprises a first pore former component and a second pore former component having a different composition than the first pore former component.

17. The batch mixture of claim 16 wherein the first pore former component is selected from a group consisting of corn starch, barley starch, bean starch, potato starch, rice starch, tapioca starch, pea starch, sago palm starch, wheat starch, canna starch, and combinations thereof.

18. The batch mixture of claim 16 wherein the second pore former component is selected from a group consisting of graphite, activated carbon, petroleum coke, carbon black, and combinations thereof.