NOVEL METAL-CONTAINING ZEOLITE BETA FOR NOx REDUCTION AND METHODS OF MAKING THE SAME

Abstract

There is disclosed an organic-free, metal-containing zeolite Beta with a silica-to-alumina ratio (SAR) ranging from 5 and 20, and a metal content of at least 0.5 wt. %. There is also disclosed a method of making such a zeolite Beta without organic structure directing agent (SDA). The metal, which may comprise Fe or Cu, can be found in amounts ranging from 1-10 wt. %. A method of selective catalytic reduction of nitrogen oxides in exhaust gases using the disclosed zeolite is also disclosed.

1 . An organic-free, metal-containing zeolite Beta with molar silica-to-alumina ratio (SAR) ranging from 5 to 20, wherein said metal comprises iron and/or copper in an amount of at least 1.0 wt. %. 
     
     
         2 . The organic-free, metal-containing zeolite Beta of  claim 1 , with the proviso that if said zeolite Beta contains any organic structure directing agent (SDA) within the pore structure it originated from the seed material during synthesis. 
     
     
         3 . The metal-containing zeolite Beta of  claim 1 , wherein said SAR ranges from 5 to 11. 
     
     
         4 . The metal-containing zeolite Beta of  claim 1 , wherein said iron or copper is introduced by liquid-phase or solid ion-exchange, impregnation, or incorporated by direct-synthesis. 
     
     
         5 . The metal-containing zeolite Beta of  claim 1 , wherein said metal comprises iron in an amount ranging from 1.0 to 10 wt. %. 
     
     
         6 . The metal-containing zeolite Beta of  claim 1 , wherein said metal comprises iron in an amount ranging from 2.0 to 10 wt. %. 
     
     
         7 . The metal-containing zeolite Beta of  claim 1 , wherein said metal comprises iron in an amount ranging from 3.0 to 8.0 wt. %. 
     
     
         8 . The metal-containing zeolite Beta of  claim 4 , where at least 60% of the iron is present as isolated cation at the exchanged site. 
     
     
         9 . The metal-containing zeolite Beta of  claim 1 , where said metal comprises copper in an amount ranging from 1.0 to 10 wt. %. 
     
     
         10 . The metal-containing zeolite Beta of  claim 1 , wherein said metal comprises copper in an amount ranging from 2.0 to 10 wt. %. 
     
     
         11 . The metal-containing zeolite Beta of  claim 1 , which exhibits an NO x  conversion of at least 40% at 200° C. for selective catalytic reduction with an ammonia generating compound after exposure to 700° C. for 16 h in the presence of up to 10 volume % of water vapor. 
     
     
         12 . The metal-containing zeolite Beta of  claim 1 , which exhibits an NO x  conversion of at least 60% at 200° C. for selective catalytic reduction with an ammonia generating compound after exposure to 700° C. for 16 h in the presence of up to 10 volume % of water vapor. 
     
     
         13 . A method of selective catalytic reduction of nitrogen oxides in exhaust gas, said method comprising:
 at least partially contacting said exhaust gases with an article comprising an organic-free, metal-containing zeolite Beta, wherein said metal comprises iron and/or copper in an amount of at least 0.5 wt. %.   
     
     
         14 . The method of  claim 13 , wherein said organic-free, metal-containing zeolite Beta has a molar silica-to-alumina ratio (SAR) ranging from 5 to 20. 
     
     
         15 . The method of  claim 14 , wherein said zeolite Beta has SAR ranging from 5 to 11. 
     
     
         16 . The method of  claim 13 , with the proviso that if said zeolite Beta contains any organic structure directing agent (SDA) within the pore structure it originated from the seed material during synthesis. 
     
     
         17 . The method of  claim 13 , wherein said contacting step is performed in the presence of ammonia, urea or an ammonia generating compound. 
     
     
         18 . The method of  claim 13 , wherein said contacting step is performed in the presence of hydrocarbon compound. 
     
     
         19 . The method of  claim 13 , wherein said copper or iron is introduced by liquid-phase or solid ion-exchange, impregnation, or incorporated by direct-synthesis. 
     
     
         20 . The method of  claim 13 , wherein said iron comprises at least 1.0 weight percent of the total weight of said material and at least 60% of the iron is present as isolated cation at the exchanged site. 
     
     
         21 . The method of  claim 13 , wherein said iron comprises an amount ranging from 1.0 to 10.0 weight percent of the total weight of said material. 
     
     
         22 . The method of  claim 13 , wherein said iron comprises an amount ranging from 2.0 to 10.0 wt. % of the total weight of said material. 
     
     
         23 . The method of  claim 13 , wherein said iron comprises an amount ranging from 3.0 to 8.0 wt. % of the total weight of said material. 
     
     
         24 . The method of  claim 13 , wherein said copper comprises an amount ranging from 1.0 to 10.0 wt. % of the total weight of said material. 
     
     
         25 . The method of  claim 13 , wherein said copper comprises an amount ranging from 2.0 to 10.0 wt. % of the total weight of said material. 
     
     
         26 . The method of  claim 13 , wherein said zeolite Beta has crystal size greater than 0.1 micron. 
     
     
         27 . The method of  claim 13 , wherein said zeolite Beta has crystal size ranging from 0.2 to 5 microns. 
     
     
         28 . The method of  claim 13 , wherein said article is in the form of a channeled or honeycombed-shaped body; a packed bed; microspheres; or structural pieces. 
     
     
         29 . The method of  claim 28 , wherein said packed bed comprises balls, pebbles, pellets, tablets, extrudates, other particles, or combinations thereof. 
     
     
         30 . The method of  claim 28 , where said structural pieces are in the form of plates or tubes. 
     
     
         31 . The method of  claim 28 , wherein the channeled or honeycombed-shaped body or structural piece is formed by extruding a mixture comprising the Beta zeolite. 
     
     
         32 . A method of synthesizing zeolite Beta with molar silica-to-alumina ratio (SAR) ranging from 5 to 20, without organic structural directing agent (SDA), excluding any seeding materials, wherein said zeolite Beta has silica utilization of greater than 30 percent from the synthesis mixture. 
     
     
         33 . The method of  claim 32 , wherein said zeolite Beta has silica utilization of greater than 50 percent from the synthesis mixture.