Nonwoven Composites and Related Products and Methods

Abstract

The present invention in certain embodiments is directed to a catalytic substrate suitable for use in a number of applications, including as a substrate in a catalytic converter or a particulate filter. Another aspect of the present invention is a filtering substrate suitable for use in a number of applications, including as a substrate in a particulate filter, such as a diesel particulate filter (DPF), or diesel particulate trap (DPT). The invention also provides an improved substrate for removing and/or eliminating pollutants from the exhaust of combustion engines. The catalytic substrate and filtering substrate provide, in certain embodiments, improvements in removing pollutants from an exhaust gas. The improvements include one or more of the following: faster light-off period, depth filtration of PM, less backpressure, lower probability of clogging, ability to be placed in multiple locations in the exhaust system including the manifold or the head itself, high probability of catalytic reaction, high conversion ratios of NOx, HC, and CO, a faster burnoff of PM, minimization of catalyst material use, and the like.

1 - 104 . (canceled) 
     
     
         105 . A method of catalyzing a reaction comprising exposing a plurality of molecules to a substrate comprising ceramic fibers bonded in a non-woven arrangement; pore space of greater than 60%: a plurality of channels; one or more catalysts; and wherein the substrate is a non-pleated construction forming a filter or catalytic converter, in an environment suitable to catalyze said reaction. 
     
     
         106 . The method according to  claim 105 , wherein said molecules are from an exhaust of an internal combustion engine. 
     
     
         107 . The method according to  claim 106 , wherein said reaction comprises an oxidation reaction, a reduction reaction, or a combination thereof. 
     
     
         108 . The method according to  claim 105 , wherein said substrate further comprises a coating. 
     
     
         109 . The method according to  claim 105 , wherein said substrate comprises an alumina enhanced thermal barrier ceramic. 
     
     
         110 . A method of effecting burn off of particulate matter, comprising:
 contacting said particulate matter with a substrate for hosting a chemical reaction, said substrate comprising:   ceramic fibers bonded in a non-woven arrangement;   pore space of greater than 60% in the substrate;   a plurality of channels in the substrate; and   wherein the substrate is a non-pleated construction; and   exposing said substrate and said particulate matter to heat sufficient to effect said burn off of said particulate matter.   
     
     
         111 . The method according to  claim 110 , wherein said heat is transferred through said composite primarily by hot gas convection. 
     
     
         112 . The method according to  claim 110 , wherein the cell density of said channels is from about 50 to about 1000 channels per square inch. 
     
     
         113 . The method according to  claim 112 , wherein the pore spaces of said substrate are heated. 
     
     
         114 . The method according to  claim 112 , wherein the efficiency of said burn off is from about 70% to about 99.9%. 
     
     
         115 . The method according to  claim 114 , wherein said particulate matter comprises PM-10 particulate matter, PM-2.5 particulate matter, and mixtures thereof. 
     
     
         116 . The method according to  claim 110 , wherein said particulate matter is from the exhaust of an internal combustion engine. 
     
     
         117 . The method according to  claim 116 , wherein said engine is a diesel engine. 
     
     
         118 . The method according to  claim 116 , wherein said substrate comprises an alumina enhanced thermal barrier ceramic having a density of from about 8 to about 16 pounds per cubic foot, pore space of about 60% to about 90%, and wherein the density of said plurality of channels is from about 50 to about 1000 channels per square inch, and the thickness of the walls of said channels is from about 1 to about 20 mils.