US 2015/0225302 A1 · IMPROVED POROUS BODIES COMPRISED OF MULLITE AND METHODS OF FORMING THEM

Abstract

A porous ceramic body useful for making particulate filters is comprised of acicular mullite grains bound together by a ceramic grain boundary phase, wherein said porous acicular mullite body has a bulk carbon content from 0.005% to 10% by weight of the body. The porous body may be made by forming a mixture of mullite precursors (e.g., alumina and silica) and a compound that is inorganic carbon (graphitic or amorphous), inorganic compound that contains carbon (e.g., metal carbide) or an organic compound that decomposes to form inorganic carbon or an inorganic compound that contains carbon and heating in an atmosphere containing fluorine to form the acicular mullite body and removing the fluorine.

Claims20

Dependent claims

A method for making a body comprised of mullite comprising,

(a) mixing one or more precursor compounds having the elements present in mullite and a carbon containing material that is:
(i) an organic compound containing carbon that decomposes to form graphitic, amorphous carbon or inorganic compound containing carbon upon heating of step (b);
(ii) graphitic carbon;
(iii) amorphous carbon;
(iv) inorganic compound containing carbon or (v) combination thereof to form a mixture,
(b) heating the mixture of step (b) under an atmosphere having a fluorine containing gas to form a porous body comprised of mullite and having fluorine in an amount greater than 1% by weight, and
(c) removing the fluorine to form the porous body comprised of mullite, wherein the amount of fluorine is less than 1% by weight of the body.

4 more elements

Dependencies are inferred from the claim text.

Improved porous bodies comprised of mullite and methods of forming them

Life of this patent

Improved porous bodies comprised of mullite and methods of forming them

Life of this patent

Abstract

Claims20