Mesoporous material and use thereof for the selective oxidation of organic compounds

Abstract

A material especially useful for the selective oxidation of hydrocarbons and other organic compounds includes a non-crystalline, porous inorganic oxide having at least 97 volume percent mesopores based on micropores and mesopores, and at least one catalytically active metal selected from the group consisting of one or more transition metal and one or more noble metal.

1 . A material which comprises: 
 a) a non-crystalline, porous inorganic oxide having at least 97 volume percent mesopores based on micropores and mesopores, said mesopores being interconnected; and    b) at least one catalytically active metal selected from the group consisting of one or more transition metal and one or more noble metal.    
     
     
         2 . The material of  claim 1  wherein the transition metal is selected from the group consisting of titanium, vanadium, copper, zirconium, manganese, zinc, iron, nickel, cobalt, chromium, molybdenum and tungsten.  
     
     
         3 . The material of  claim 1  wherein the noble metal is selected from the group consisting of gold, silver, platinum, palladium, iridium, rhodium, ruthenium, rhenium and osmium.  
     
     
         4 . The material of  claim 1  wherein the catalytically active metal is gold or silver.  
     
     
         5 . The material of  claim 1  wherein the catalytically active metal is chromium.  
     
     
         6 . The material of  claim 1  wherein the catalytically active metal is titanium.  
     
     
         7 . The material of  claim 1  wherein the non-crystalline porous inorganic oxide is characterized by an X ray diffraction pattern having a 2θ peak between 0.5° and 2.5°.  
     
     
         8 . The material of  claim 1  wherein the non-crystalline porous inorganic oxide contains at least 98 volume percent mesopores.  
     
     
         9 . The material of  claim 1  wherein the mesopores have a size ranging from about 2 nm to about 25 nm.  
     
     
         10 . The material of  claim 1  wherein the inorganic oxide is silicon oxide.  
     
     
         11 . The material of  claim 1  wherein the inorganic oxide is aluminum oxide.  
     
     
         12 . The material of  claim 1  wherein the composition percentage by weight of the transition metal ranges up to about 60%.  
     
     
         13 . The material of  claim 1  wherein the composition by weight of the transition metal ranges from about 0.001% to about 20%.  
     
     
         14 . The material of  claim 1  wherein the composition percentage by weight of the noble metal ranges up to about 60%.  
     
     
         15 . The material of  claim 1  wherein the composition percentage by weight of the noble metal ranges from about 0.1% to about 40%.  
     
     
         16 . A method for making a catalyst comprising the steps of: 
 a) combining at least one source of inorganic oxide and at least one mesopore forming agent and optionally one or more source of catalytically active transition metal to form a synthesis mixture;    b) drying the synthesis mixture;    c) heating the dried synthesis mixture to a calcining temperature for a period of time sufficient to form a non-crystalline support structure having at least 97 volume percent mesopores; and,    d) incorporating at least one catalytically active noble metal and/or transition metal into the catalyst.    
     
     
         17 . The method of  claim 16  wherein the inorganic oxide is selected from the group consisting of aluminum oxide and silicon oxide.  
     
     
         18 . The method of  claim 17  wherein the source of inorganic oxide is selected from the group consisting of silicon alkoxide and aluminum alkoxide.  
     
     
         19 . The method of  claim 18  wherein the silicon alkoxide is tetraethyl orthosilicate and the aluminum alkoxide is aluminum isopropoxide.  
     
     
         20 . The method of  claim 16  wherein the catalytically active transition metal is incorporated into the catalyst by combining a compound containing the transition metal with the source of inorganic oxide in step (a) to form the synthesis mixture.  
     
     
         21 . The method of  claim 16  wherein the catalytically active transition metal is incorporated into the catalyst by incorporating a compound containing the transition metal into the catalyst after step (c) of heating the dried synthesis mixture to a calcining temperature.  
     
     
         22 . The method of  claim 16  wherein the transition metal is selected from the group consisting of titanium, vanadium, copper, zirconium, manganese, zinc, chromium, molybdenum, tungsten, nickel, cobalt and iron.  
     
     
         23 . The method of  claim 20  wherein the compound containing the transition metal is an alkoxide of titanium.  
     
     
         24 . The method of  claim 23  wherein the alkoxide of titanium is titanium n-butoxide.  
     
     
         25 . The method of  claim 16  wherein heating the dried synthesis mixture to a calcining temperature includes heating the dried synthesis mixture to a temperature of from about 120° C. to about 200° C. for a period of time of about from 2 hours to about 96 hours.  
     
     
         26 . The method of  claim 16  wherein the noble metal is selected from the group consisting of gold, silver, platinum, palladium, iridium, rhodium, ruthenium, rhenium and osmium.  
     
     
         27 . The method of  claim 16  wherein the step (d) of incorporating at least one catalytically active noble metal or transition metal into the catalyst comprises impregnating the non-crystalline support structure with a solution of a soluble, decomposable compound of the noble metal and/or transition metal, and thereafter decomposing the noble metal compound and/or transition metal compound.  
     
     
         28 . The method of  claim 27  wherein the step of decomposing the noble metal compound and/or transition metal compound comprises calcining the noble metal and/or transition metal impregnated non-crystalline support at a temperature sufficient to decompose the noble metal compound and/or transition metal compound.  
     
     
         29 . The method of  claim 28  wherein the noble metal is gold or silver.  
     
     
         30 . The method of  claim 16  wherein the mesopore forming agent is selected from the group consisting of glycerol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, triethanolamine, sulfolane, tetraethylene pentamine and diethylglycol dibenzoate.  
     
     
         31 . The method of  claim 16  wherein the step (d) of incorporating at least one catalytically active noble metal and/or transition metal comprises incorporating both a catalytically active noble metal and transition metal into the catalyst.  
     
     
         32 . A process for the selective oxidation of an organic compound comprising: 
 contacting the organic compound with an oxidizing agent under partial oxidation reaction conditions in the presence of a catalyst which includes a non-crystalline, porous inorganic oxide having at least 97 volume percent mesopores based on micropores and mesopores, and at least one catalytically active metal selected from the group consisting of one or more transition metal and one or more noble metal.    
     
     
         33 . (canceled)  
     
     
         34 . (canceled)  
     
     
         35 . (canceled)  
     
     
         36 . The process of  claim 32  wherein the organic compound is an alkane and the selective oxidation process is the partial oxidation of the alkane to produce a corresponding ketone or alcohol.  
     
     
         37 . The process of  claim 36  wherein the alkane is selected from the group consisting of propane, butane, pentane and cyclohexane, the oxidizing agent is selected from the group consisting of oxygen, oxygen-containing gas, hydrogen peroxide, nitrogen oxide, organic hydroperoxide and organic peracid, and the reaction conditions include a temperature of from about 0° C. to about 200° C., a pressure of from about 1 bar to about 30 bars, and a space velocity of from about 100 hr −1  to about 1000 hr −1 .  
     
     
         38 . The process of  claim 32  wherein the organic compound is a ketone and the selective oxidation process is the ammoximation of the ketone to produce a corresponding oxime.  
     
     
         39 . The process of  claim 38  wherein the ketone is selected from the group consisting of acetone, methylethyl ketone, acetophenone, cyclohexanone and cyclododecanone, the oxidizing agent is hydrogen peroxide or nitrogen oxide which is mixed with ammonia, and the reaction conditions include a temperature of from about 25° to about 150°, and a pressure of from about 1 atmosphere to about 10 atmospheres.  
     
     
         40 . The process of  claim 32  wherein the organic compound is an aromatic compound and the selective oxidation process is the hydroxylation of the aromatic compound to add at least one hydroxyl group to the aromatic ring structure.  
     
     
         41 . The process of  claim 40  wherein said aromatic compound is selected from the group consisting of benzene and toluene, and the oxidizing agent is selected from the group consisting of oxygen, oxygen-containing gas, hydrogen peroxide, nitrogen oxide, organic hydroperoxide and organic per-acid, and the reaction conditions include a temperature of from 125° C. to about 500° C. and a pressure up to 65 bars.  
     
     
         42 . The process of  claim 32  wherein the catalytically active transition metal is selected from the group consisting of titanium, vanadium and chromium.  
     
     
         43 . The process of  claim 32  wherein the catalytically active noble metal is gold or silver.