Supported catalyst for purifying gas and method of manufacturing the same

Abstract

The present invention discloses an improved supported catalyst for gas purification which comprises a catalyst carrier composed of a molded body including alumina cement having a CaO component in an amount of less than 40% by weight, an Al 2 O 3 component in an amount of more than 35% by weight and an iron oxide component in an amount of less than 20% by weight. Additionally, catalytic materials and auxiliary materials may be added, depending on necessity. A platinum group metal is then supported on the catalyst carrier. There is also disclosed a method for manufacturing such catalyst. .Iadd.

What is claimed is: 
     
       1. A catalyst for use in purification of a gas which comprises a catalyst carrier composed of alumina cement having a CaO component of less than 40% by weight, an Al 2  O 3  component of more than 35% by weight and a Fe 2  O 3  component of less than 20% by weight and at least one aggregate selected from the group consisting of silica aggregate, silica-alumina aggregate, and alumina aggregate, and a platinum group metal supported on said catalyst carrier in an amount of 0.001 to 0.1% by weight, said catalyst being produced by the steps comprising: a. molding a molded body from a mixture comprising alumina cement and said aggregate;   b. curing said molded body for the hardening thereof,   c. subsequently .Iadd.drying and/or .Iaddend.heat treating said hardened molded body .[.at a temperature range from 250° to 700° C..]. to obtain a catalyst carrier; and   d. causing a platinum group metal to be supported on said catalyst carrier by steps comprising:   1. contacting said carrier with a solution of a salt of said platinum group metal to impregnate said solution on the surface of said carrier; and   2. subsequently heat treating said catalyst impregnated carrier at a temperature .[.below.]. .Iadd.from 250° to .Iaddend.700° C. to convert said platinum group metallic salt into a platinum group metal.   
     
     
       2. .[.A.]. .Iadd.The .Iaddend.catalyst as claimed in claim 1, wherein said catalyst carrier further includes at least one oxide of manganese and copper. 
     
     
       3. .[.A.]. .Iadd.The .Iaddend.catalyst as claimed in claim 1 wherein said catalyst carrier includes at least one member selected from the group consisting of ferrites and zeolites. 
     
     
       4. .[.A.]. .Iadd.The .Iaddend.catalyst as claimed in claim 1, wherein said catalyst carrier further includes an auxiliary agent composed of at least one of asbestos and glass fiber. 
     
     
       5. A method of manufacturing a supported catalyst as claimed in claim 1, further employing a solvent medium for said solution of platinum group metallic salt, which medium is at least one member selected from the group of water and alcohol. .Iadd. 6. The catalyst as claimed in claim 1, wherein said drying step is carried at a temperature of 80° C. .Iaddend..Iadd. 7. The catalyst as claimed in claim 1, wherein said heat treating step c. is carried at a temperature range from 250° to 700° C. .Iaddend.