Chemically functionalized filter system

Abstract

A filter for engine exhaust gases includes a filter media having an internal and external surface. A plurality of molecules of a fluid catalyst are attached to at least the internal and external surface of the filter media. The molecules of the fluid catalyst are configured to donate an oxygen atom to soot particles to activate the soot particles for regeneration.

1 . A filter for engine exhaust gases, comprising;
 a filter media having an internal and external surface; and   a plurality of molecules of a fluid catalyst attached to the filter media, wherein the molecules of the fluid catalyst are
 attached to at least the internal and external surface of the filter media, and 
 configured to donate an oxygen atom to soot particles to activate the soot particles for regeneration. 
   
   
   
       2 . The filter of  claim 1 , wherein the molecules of the fluid catalyst are configured to regain an original chemical composition by taking an oxygen atom from oxygen in the exhaust gases. 
   
   
       3 . The filter of  claim 1 , wherein the fluid catalyst is a gas. 
   
   
       4 . The filter of  claim 3 , wherein the gas includes nitrogen dioxide (NO 2 ). 
   
   
       5 . The filter of  claim 4 , wherein the nitrogen dioxide (NO 2 ) is configured to change to nitrous oxide (NO) after donating an oxygen atom to a soot particle contained in the engine exhaust gases. 
   
   
       6 . The filter of  claim 5 , wherein the nitrous oxide (NO) is configured to change back to nitrogen dioxide (NO 2 ) after taking an oxygen atom from oxygen in the engine exhaust gases. 
   
   
       7 . The filter of  claim 1 , wherein the molecules of the fluid catalyst are attached to the filter media by adsorption. 
   
   
       8 . The filter of  claim 1 , wherein the filter media includes at least one of ceramic cordierite, woven fiber cartridges, knitted silica fiber coils, ceramic foam, wire mesh, and sintered metal substrates. 
   
   
       9 . The filter of  claim 1 , wherein the external surface of the filter media include at least two opposing surface portions of the filter media, and the internal surface of the filter media includes at least the surface portions inside pores of the filter media. 
   
   
       10 . A method of regenerating a filter comprising;
 chemically functionalizing a filter media of the filter with molecules of a fluid catalyst;   flowing the exhaust gases through the filter;   accumulating the soot particles in the filter media;   activating the accumulated soot particles by donating oxygen atoms from the catalyst to at least some of the accumulated soot particles; and   regenerating the filter by burning the activated soot particles.   
   
   
       11 . The method of  claim 10 , wherein activating the accumulated soot particles includes changing the chemical composition of the catalyst after donation of the oxygen atoms. 
   
   
       12 . The method of  claim 11 , wherein activating the accumulated soot particles further include regaining the chemical composition of the catalyst by taking oxygen atoms from oxygen in the engine exhaust. 
   
   
       13 . The method of  claim 10 , wherein chemical functionalization includes functionalizing the filter media with molecules of a gaseous catalyst. 
   
   
       14 . The method of  claim 10 , wherein chemical functionalization includes functionalizing the filter media with molecules of nitrogen dioxide (NO 2 ). 
   
   
       15 . The method of  claim 14 , wherein activating the accumulated soot particles includes changing the nitrogen dioxide (NO 2 ) to nitrous oxide (NO) after donating an oxygen atoms. 
   
   
       16 . The method of  claim 15 , wherein activating the accumulated soot particles further includes changing the nitrous oxide (NO) to nitrogen dioxide (NO 2 ) by taking oxygen atoms from oxygen in the engine exhaust. 
   
   
       17 . The method of  claim 10 , wherein chemical functionalization includes adsorption of the fluid catalyst on the filter media. 
   
   
       18 . The method of  claim 10 , wherein regeneration of the filter occurs at a temperature below 600° C. 
   
   
       19 . The method of operating an internal combustion engine comprising;
 exhausting from the engine exhaust gas containing soot particles;   flowing the exhaust gas through a filter having a filter media chemically functionalized with a gaseous catalyst;   collecting soot particles on the filter media;   activating the collected soot particles by donating oxygen atoms from the gaseous catalyst to at least some of the collected soot particles;   replenishing the gaseous catalyst by taking oxygen atoms from oxygen contained in the exhaust gas; and   regenerating the filter by burning the activated soot particles.   
   
   
       20 . The method of  claim 19 , wherein the regeneration of the filter occurs at a temperature below 600° C.