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A method for uniformly dispersing noble metal particles on a porous carrier by first mixing an alkoxide product of aluminum or silicon and a noble metal precursor together; then mixing a surfactant into the mixture; then mixing ammonia solution into the mixture to form a hydroxide of aluminum or sil

A method for uniformly dispersing noble metal particles on a porous carrier by first mixing an alkoxide product of aluminum or silicon and a noble metal precursor together; then mixing a surfactant into the mixture; then mixing ammonia solution into the mixture to form a hydroxide of aluminum or silicon; then mixing a reducing agent into the mixture to convert the noble metal precursor into noble metal nanoparticles dispersed on the hydroxide; then separating the noble metal nanoparticles and the hydroxide from the mixture before calcining the hydroxide into an oxide of aluminum or silicon.

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What is claimed is: 1. A method for uniformly dispersing noble metal particles on a porous carrier comprising the sequential steps of: mixing an oxidation product of aluminum or silicon and a noble metal precursor forming a first mixture; mixing a surfactant into said first mixture forming a second

What is claimed is: 1. A method for uniformly dispersing noble metal particles on a porous carrier comprising the sequential steps of: mixing an oxidation product of aluminum or silicon and a noble metal precursor forming a first mixture; mixing a surfactant into said first mixture forming a second mixture; mixing ammonia solution into said second mixture forming a third mixture containing a hydroxide of aluminum or silicon; mixing a reducing agent into said third mixture converting said noble metal precursor into noble metal particles each having a particle size not larger than 10 nm dispersed on said hydroxide; separating said noble metal particles and said hydroxide from said third mixture; and calcining said hydroxide into an oxide of aluminum or silicon. 2. A method for uniformly dispersing noble metal particles on a porous carrier according to claim 1 further comprising the step of converting into said noble metal particles each having a particle size not larger than 5 nm. 3. A method for uniformly dispersing noble metal particles on a porous carrier according to claim 1 further comprising the step of washing and drying prior to said calcining step. 4. A method for uniformly dispersing particles of noble metal on an aluminum oxide carrier comprising the sequential steps of: mixing an organoaluminum and a noble metal precursor forming a first mixture; adding a surfactant into said first mixture forming a second mixture; mixing ammonia solution into said second mixture forming a third mixture containing aluminum hydroxide; mixing a reducing agent into said third mixture converting said noble metal precursor into noble metal particles each having a particle size not larger than 10 nm dispersed on said aluminum hydroxide; separating said noble metal particles and said aluminum hydroxide from said second mixture; calcining said aluminum hydroxide into aluminum oxide; and wherein said first mixture contains between 25 mmol/l and 450 mmol/l of said organoaluminum. 5. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 4, wherein said organoaluminum is selected from the group consisting of aluminum ethoxide, aluminum isopropoxide, aluminum sec-butoxide, aluminum tert-butoxide and aluminum isobutoxide. 6. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 4 further comprising the step of forming said noble metal precursor by dissolving a noble metal compound in water or an organic solvent. 7. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 6, wherein said organic solvent is selected from the group consisting of ethanol, cyclohexane, n-hexane, chloroform and acetone. 8. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 4, wherein said noble metal particles are selected from the group consisting of gold, silver, copper, cobalt, nickel and platinum. 9. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 4, wherein said ammonia solution is a 3-10 wt. % ammonia solution. 10. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 4, wherein said second mixture containing said surfactant at a molar ratio with aluminum between 1:1 and 1:10. 11. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 4, wherein said second mixture containing said reducing agent at a molar ratio with said noble metal between 5:1 and 20:1. 12. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 4, wherein said surfactantis a non-iomc surfactant selected from the group consisting of polyglycol and polyethylene glycols of polyoxyethylene alkyl phenol ether, polypropylene glycol/polyethanol reactant product, fatty alcohol-polyoxyethylene ethers and fatty acid-polyoxyethylene. 13. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 12, wherein said surfactant is a non-ionic surfactant selected from the group consisting of polyglycol and polyethylene glycols of polyoxyethylene alkyl phenol ether, polypropylene glycol/polyethanol reactant product, fatty alcohol-polyoxyethylene ethers and fatty acid-polyoxyethylene. 14. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 4, wherein said surfactant is a cationic surfactant selected from the group consisting of cetyltrimethyl ammonium bromide (CTAB), cetyltrimethyl ammonium chloride (CTAC) and C 10-C20 long-chain alkyl ammonium. 15. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 4, wherein said reducing agent is selected from the group consisting of hydrazine, hydrazine sulfate and boron hydride. 16. A method for uniformly dispersing particles of noble metal on a silicon oxide carrier comprising the sequential steps of: mixing silane oxide and a noble metal precursor forming a first mixture; mixing ethanol, ammonia solution and a surfactant forming a second mixture; mixing by adding said first mixture into said second mixture forming a silicon hydroxide gel in a third mixture; adding a reducing agent into said third mixture converting said noble metal precursor into noble metal particles each having a particle size not larger than 10 nm dispersed on said silicon hydroxide; separating said noble metal particles and said silicon hydroxide from said third mixture; calcining said silicon hydroxide into silicon oxide; and wherein said third mixture contains silane oxide, ethanol, ammonia solution and surfactant at a molar ratio of 1:40-100:0.5-2:0.5-5. 17. A method for uniformly dispersing particles of noble metal on a silicon oxide carrier according to claim 16 further comprising the step of forming said noble metal precursor by dissolving a noble metal compound in water or an organic solvent. 18. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 17, wherein said organic solvent is selected from the group consisting of ethanol, cyclohexane, n-hexane, chloroform and acetone. 19. A method for uniformly dispersing particles of noble metal on a silicon oxide carrier according to claim 16 wherein said third mixture containing said reducing agent at a molar ratio with said noble metal between 5:1 and 20:1. 20. A method for uniformly dispersing particles of noble metal on a silicon oxide carrier according to claim 16 wherein said silane oxide is selected from the group consisting of ethyl orthosilicate (C4-C16 silicate ester), methyl orthosilicate, propyl orthosilicate and butyl orthosilicate. 21. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 16, wherein said noble metal particles are selected from the group consisting of gold, silver, copper, cobalt, nickel and platinum. 22. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 16, wherein said ammonia solution is a 3-10 wt. % ammonia solution. 23. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 16, wherein said surfactant is a cationic surfactant selected from the group consisting of cetyltrimethyl ammonium bromide (CTAB), cetyltrimethyl amnionium chloride (CTAC) and C10-C20 long-chain alkyl ammonium. 24. A method for uniformly dispersing noble metal particles on aluminum oxide according to claim 16, wherein said reducing agent is selected from the group consisting of hydrazine, hydrazine sulfate and boron hydride.