Catalyst Design for Heavy-Duty Diesel Combustion Engines

Abstract

Disclosed are washcoats, coated substrates formed from such washcoats, and catalytic converters for use in diesel applications, such as heavy duty diesel applications. Methods of preparing the coated substrates are also disclosed.

1 . The coated substrate of  claim 5 , wherein the coated substrate is free of zeolites, first catalytically active material further comprises plasma-created composite nanoparticles bonded to or embedded within micron-sized carrier particles, the composite nanoparticles comprising a support nanoparticle and a catalytic nanoparticle, and the second catalytically active material further comprises plasma-created composite nanoparticles bonded to or embedded within micron-sized carrier particles, the composite nanoparticles comprising a support nanoparticle and a catalytic nanoparticle. 
     
     
         2 . (canceled) 
     
     
         3 . The coated substrate of  claim 5 , wherein the coated substrate is free of zeolites, and wherein the first catalytically active material comprises plasma-created composite nanoparticles bonded to or embedded within micron-sized carrier particles, the composite nanoparticles comprising a support nanoparticle and a catalytic nanoparticle. 
     
     
         4 . (canceled) 
     
     
         5 . A coated substrate comprising:
 a substrate;   a first washcoat layer comprising:
 boehmite particles; and 
 a first catalytically active material comprising platinum and palladium in a weight ratio of 10:1 platinum:palladium to 100:1 platinum:palladium, or comprising platinum and no palladium; and 
   a second washcoat layer comprising:
 boehmite particles; and 
 a second catalytically active material comprising platinum and palladium in a weight ratio of 1:2 platinum:palladium to 8:1 platinum:palladium, or comprising two or more catalytically active materials which together comprise platinum and palladium in a weight ratio of 1:2 platinum:palladium to 8:1 platinum:palladium, or comprising palladium and no platinum. 
   
     
     
         6 . (canceled) 
     
     
         7 . The coated substrate of  claim 5 , wherein the coated substrate is substantially free of zeolites. 
     
     
         8 - 9 . (canceled) 
     
     
         10 . The coated substrate of  claim 5 , wherein the first washcoat layer is coated on the substrate prior to the coating of the second washcoat layer. 
     
     
         11 . The coated substrate of  claim 5 , wherein the second washcoat layer is coated on the substrate prior to the coating of the first washcoat layer. 
     
     
         12 . The coated substrate of  claim 5 , wherein the first catalytically active material comprises plasma-created composite nanoparticles bonded to pre-formed micron-sized carrier particles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle. 
     
     
         13 . The coated substrate of  claim 5 , wherein the first catalytically active material comprises micron-sized particles comprising plasma-created composite nanoparticles and a carrier matrix formed around the nanoparticles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle. 
     
     
         14 . The coated substrate of  claim 5 , wherein the first catalytically active material comprises hybrid particles comprising plasma-created composite nanoparticles bonded to pre-formed micron-sized carrier particles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle, and wherein the micron-sized pre-formed carrier particles are impregnated by wet-chemistry methods with platinum or platinum:palladium alloy. 
     
     
         15 . (canceled) 
     
     
         16 . The coated substrate of  claim 5 , wherein the second catalytically active material comprises plasma-created composite nanoparticles bonded to pre-formed micron-sized carrier particles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle. 
     
     
         17 . The coated substrate of  claim 5 , wherein the second catalytically active material comprises micron-sized particles comprising plasma-created composite nanoparticles and a carrier matrix formed around the nanoparticles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle. 
     
     
         18 . The coated substrate of  claim 5 , wherein the second catalytically active material comprises hybrid particles comprising plasma-created composite nanoparticles bonded to pre-formed micron-sized carrier particles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle, and wherein the micron-sized pre-formed carrier particles are impregnated by wet-chemistry methods with palladium or platinum:palladium alloy. 
     
     
         19 . (canceled) 
     
     
         20 . The coated substrate of  claim 5 , wherein:
 the second washcoat layer comprises two or more catalytically active materials which together comprise platinum and palladium in a weight ratio of 1:2 platinum:palladium to 8:1 platinum:palladium; and   the two or more catalytically active materials together comprising platinum and palladium in a weight ratio of 1:2 platinum:palladium to 8:1 platinum:palladium comprise:   i) a catalyst comprising platinum:palladium alloy in a ratio of about 15:1 Pt:Pd to about 25:1 Pt:Pd; and   ii) a catalyst comprising palladium.   
     
     
         21 . The coated substrate of  claim 5 , wherein:
 the second washcoat layer comprises two or more catalytically active materials which together comprise platinum and palladium in a weight ratio of 1:2 platinum:palladium to 8:1 platinum:palladium; and   the two or more catalytically active materials together comprising platinum and palladium in a weight ratio of 1:2 platinum:palladium to 8:1 platinum:palladium comprise
 a) plasma-created composite nanoparticles bonded to pre-formed micron-sized carrier particles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle, wherein the catalytic nanoparticle comprises a Platinum:palladium alloy in a ratio of about 15:1 Pt:Pd to about 25:1 Pt:Pd; and 
 b) a catalyst comprising palladium. 
   
     
     
         22 . The coated substrate of  claim 5 , wherein the two or more catalytically active materials together comprising platinum and palladium in a weight ratio of 1:2 platinum:palladium to 8:1 platinum:palladium comprise:
 a) micron-sized particles comprising plasma-created composite nanoparticles and a carrier matrix formed around the nanoparticles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle, wherein the catalytic nanoparticle comprises a platinum:palladium alloy in a ratio of about 15:1 Pt:Pd to about 25:1 Pt:Pd; and   b) micron-sized carrier particles impregnated with palladium by wet-chemistry methods.   
     
     
         23 . The coated substrate of  claim 5 , wherein the two or more catalytically active materials together comprising platinum and palladium in a weight ratio of 1:2 platinum:palladium to 8:1 platinum:palladium comprise:
 a) hybrid particles comprising plasma-created composite nanoparticles bonded to pre-formed micron-sized carrier particles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle, and wherein the micron-sized pre-formed carrier particles are impregnated by wet-chemistry methods with palladium or platinum:palladium alloy, wherein the hybrid particles comprise a total content of platinum:palladium in a ratio of about 15:1 Pt:Pd to about 25:1 Pt:Pd; and   b) micron-sized carrier particles impregnated with palladium by wet-chemistry methods.   
     
     
         24 - 36 . (canceled) 
     
     
         37 . The coated substrate of  claim 5 , wherein the washcoat layer or washcoat layers comprise 1% to 20% boehmite particles by weight. 
     
     
         38 - 41 . (canceled) 
     
     
         42 . The coated substrate of  claim 5 , wherein the washcoat layer comprising the second catalytically active material further comprises a third catalytically active material selected from the group consisting of:
 plasma-created composite nanoparticles bonded to pre-formed micron-sized carrier particles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle;   plasma-created composite nanoparticles and a carrier matrix formed around the nanoparticles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle;   hybrid particles comprising plasma-created composite nanoparticles bonded to pre-formed micron-sized carrier particles, wherein the composite nanoparticles comprise a support nanoparticle and a catalytic nanoparticle, and wherein the micron-sized pre-formed carrier particles are impregnated by wet-chemistry methods with platinum, palladium, or platinum:palladium alloy; and   catalytic particles produced by only wet-chemistry methods, comprising a micron-sized particle impregnated by only wet-chemistry methods with platinum, palladium, or platinum:palladium alloy;   wherein said third catalytically active material is different from the second catalytically active material.   
     
     
         43 . The coated substrate of  claim 42 , wherein the third catalytically active material comprises platinum and no palladium. 
     
     
         44 . The coated substrate of  claim 42 , wherein the third catalytically active material comprises platinum and palladium at a platinum:palladium ratio of 10:1 to 100:1. 
     
     
         45 - 96 . (canceled)