Porous ceramic article and method of manufacturing the same

Abstract

The present disclosure relates to porous ceramic articles and a method of making the same. The porous ceramic articles have microstructure of sinter bonded or reaction bonded large pre-reacted particles and pore network structure exhibiting large pore necks. The method of making the porous ceramic articles involves using pre-reacted particles having one or more phases. A plastic ceramic precursor composition is also disclosed. The composition includes a mixture of at least one of dense, porous, or hollow spheroidal pre-reacted particles and a liquid vehicle.

What is claimed is: 
     
         1 . A method of making a porous ceramic article comprising pre-reacted particles, the method comprising:
 forming green particles;   calcining the green particles to form pre-reacted particles, wherein (i) the pre-reacted particles comprise at least one of dense, porous, or hollow particles, (ii) the pre-reacted particles comprise a spheroidal shape, (iii) the pre-reacted particles have a multiphase composition, and (iv) the multiphase composition of the pre-reacted particles comprises at least two of aluminum titanate solid solution pseudobrookite, cordierite, mullite, spinel, feldspar, alumina, silica, rutile, and glass;   mixing the pre-reacted particles and a liquid vehicle to form a paste;   forming the paste into a wet green body;   drying the wet green body to form a dried green body; and   firing the dried green body to form the porous ceramic article.   
     
     
         2 . The method of  claim 1 , wherein forming green particles comprises forming green particles of at least 10 μm diameter. 
     
     
         3 . The method of  claim 1 , wherein forming green particles comprises:
 mixing at least two inorganic fine powders with a liquid vehicle to make a slurry, and spray-drying the slurry.   
     
     
         4 . The method of  claim 3 ,
 wherein the at least two inorganic fine powders comprise a first inorganic fine powder comprising a source of alumina, a source of silica, a source of magnesia, a source of titania, strontium oxide, barium oxide, calcium oxide, lanthanum oxide, boron oxide, cerium oxide, yttrium oxide, other rare earth oxide, zirconium oxide, alkali oxide, or iron oxide; and   wherein the at least two inorganic fine powders comprise a second inorganic fine powder different from the first inorganic fine powder and the second inorganic fine powder comprises a source of alumina, a source of silica, a source of magnesia, a source of titania, strontium oxide, calcium oxide, lanthanum oxide, boron oxide, cerium oxide, yttrium oxide, other rare earth oxide, zirconium oxide, or alkali oxide.   
     
     
         5 . The method of  claim 3 , wherein the inorganic fine powders comprise an average particle in a range of 1×10 −9  to 5.0×10 −6  meters 
     
     
         6 . The method of  claim 1 , wherein calcining green particles to form pre-reacted particles comprises forming at least one of partially reacted and fully reacted particles. 
     
     
         7 . The method of  claim 1 , wherein forming the paste comprises extruding the paste into a green honeycomb log. 
     
     
         8 . The method of  claim 1 , wherein the porous ceramic article comprises greater than 50 vol % of aluminum titanate solid solution pseudobrookite. 
     
     
         9 . The method of  claim 1 , wherein the porous ceramic article comprises a microstructure of (i) solid matter comprising bonded spheroidal particles and (ii) a network of contiguous pores with large pore necks. 
     
     
         10 . A method of making a porous ceramic article, comprising:
 forming green particles;   calcining the green particles to form pre-reacted particles, wherein (i) the pre-reacted particles have a multiphase composition, and (ii) the multiphase composition of the pre-reacted particles comprises at least two of aluminum titanate solid solution pseudobrookite, cordierite, mullite, spinel, feldspar, alumina, silica, rutile, and glass;   mixing the pre-reacted particles, polymer beads, and a liquid vehicle to form a paste;   forming the paste into a wet green body;   drying the wet green body to form a dried green body; and   firing the dried green body to form the porous ceramic article.   
     
     
         11 . The method of  claim 10 , wherein forming green particles comprises forming green particles of at least 10 μm diameter. 
     
     
         12 . The method of  claim 10 , wherein the pre-reacted particles comprise at least one of dense, porous, or hollow particles, and the pre-reacted particles comprise a spheroidal shape. 
     
     
         13 . The method of  claim 10 , wherein the pre-reacted particles are fully reacted. 
     
     
         14 . The method of  claim 10 , wherein the forming green particles comprises:
 mixing at least two inorganic fine powders with liquid vehicle to make a slurry, and spray-drying the slurry.   
     
     
         15 . The method of  claim 14 , wherein each of the inorganic fine powders comprises an average particle diameter in a range of 1×10 −9  to 5.0×10 −6  meters. 
     
     
         16 . The method of  claim 15 ,
 wherein the at least two inorganic fine powders comprise a first inorganic fine powder comprising a source of alumina, a source of silica, a source of magnesia, a source of titania, strontium oxide, barium oxide, calcium oxide, lanthanum oxide, boron oxide, cerium oxide, yttrium oxide, other rare earth oxide, zirconium oxide, alkali oxide, or iron oxide; and   wherein the at least two inorganic fine powders comprise a second inorganic fine powder different from the first inorganic fine powder and the second inorganic fine powder comprises a source of alumina, a source of silica, a source of magnesia, a source of titania, strontium oxide, calcium oxide, lanthanum oxide, boron oxide, cerium oxide, yttrium oxide, other rare earth oxide, zirconium oxide, or an alkali oxide.   
     
     
         17 . The method of  claim 10 , wherein the polymer beads have a particle size to match a particle size of the pre-reacted particles 
     
     
         18 . The method of  claim 10 , wherein the porous ceramic article comprises greater than 50 vol % of aluminum titanate solid solution pseudobrookite phase. 
     
     
         19 . The method of  claim 10 , wherein the calcining of the pre-reacted particles further comprises rotary calcination at between 1000° C. and 1650° C. 
     
     
         20 . The method of  claim 10 , wherein the porous ceramic article comprises a porosity of at least 50% and a median pore size of 10 μm to 30 μm. 
     
     
         21 . The method of  claim 10 , wherein the porous ceramic article comprises a microstructure of (i) solid matter comprising bonded spheroidal particles and (ii) a network of contiguous pores with large pore necks.