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A method for preparing supported palladium-gold catalysts is disclosed. The method comprises increasing the porosity of a titanium dioxide support, impregnating the support with a palladium salt, a gold salt, and an optional alkali metal or ammonium compound, and reducing the calcined support. The r

A method for preparing supported palladium-gold catalysts is disclosed. The method comprises increasing the porosity of a titanium dioxide support, impregnating the support with a palladium salt, a gold salt, and an optional alkali metal or ammonium compound, and reducing the calcined support. The resultant supported palladium-gold catalysts have increased activity in the acetoxylation.

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I claim: 1. A method for preparing a supported palladium-gold catalyst, said method comprising (a) increasing a titanium dioxide support intrusion volume to greater than or equal to 0.31 milliliter of mercury per gram by mixing two titanias which have different sizes, or by mixing a sintered titani

I claim: 1. A method for preparing a supported palladium-gold catalyst, said method comprising (a) increasing a titanium dioxide support intrusion volume to greater than or equal to 0.31 milliliter of mercury per gram by mixing two titanias which have different sizes, or by mixing a sintered titania with a non-sintered titania, or by mixing a spray-dried titania with a non-spray dried titania; impregnating the support with a palladium salt, gold salt, and an optional alkali metal or ammonium compound; and (b) reducing the impregnated support to form the supported palladium-gold catalyst. 2. The method of claim 1, wherein the titanium dioxide support has a total intrusion volume of greater than or equal to 0.35 milliliter per gram. 3. The method of claim 1, wherein the titanium dioxide support has a total intrusion volume of greater than or equal to 0.40 milliliter per gram. 4. The method of claim 1, wherein the alkali metal or ammonium compound in selected from the group consisting of hydroxides, carbonates, bicarbonates, metasilicates, and mixtures thereof. 5. The method of claim 1, wherein the alkali metal or ammonium compound is a carbonate or bicarbonate. 6. The method of claim 1, wherein the palladium salt is selected from the group consisting of palladium chloride, sodium chloropalladite, palladium nitrate, and palladium sulfate; and the gold salt is selected from the group consisting of auric chloride, tetrachloroauric acid, sodium tetrachloroaurate, and mixtures thereof 7. A method for preparing a supported palladium-gold catalyst, said method comprising (a) increasing a titanium dioxide support intrusion volume to greater than or equal to 0.31 milliliter of mercury per gram by mixing two titanias which have different sizes, or by mixing a sintered titania with a non-sintered titania, or by mixing a spray-dried titania with a non-spray dried titania; impregnating the support with a palladium salt, gold salt, and an alkali metal or ammonium compound; (b) calcining the impregnated support; and (c) reducing the calcined support to form the supported palladium-gold catalyst. 8. The method of claim 7, wherein the calcination is performed in a non-reducing atmosphere at a temperature within the range of 100° C. to 600° C. 9. The method of claim 8, wherein the non-reducing atmosphere is selected from the group consisting of helium, nitrogen, argon, neon, nitrogen oxides, oxygen, air, carbon dioxide, and mixtures thereof. 10. The method of claim 9, wherein the calcination temperature is within the range of 100° C. to 300° C. 11. The method of claim 7, wherein the reduction is performed in the presence of hydrogen. 12. The method of claim 11, wherein the reduction is performed at a temperature within the range of 300° C. to 600° C. 13. The method of claim 11, wherein the reduction is performed at a temperature within the range of 450° C. to 550° C. 14. The method of claim 7, which farther comprises (d) treating the supported palladium-gold catalyst with a potassium salt. 15. A method for preparing a supported palladium-gold catalyst, said method comprising (a) increasing a titanium dioxide support intrusion volume to greater than or equal to 0.31 milliliter of mercury per gram by mixing two titanias which have different sizes, or by mixing a sintered titania with a non-sintered titania, or by mixing a spray-dried titania with a non-spray dried titania; calcining the titanium dioxide support; (b) impregnating the calcined support with a palladium salt, a gold salt, and an alkali metal or ammonium compound; (c) calcining the impregnated support; and (d) reducing the calcined support from step (c) to form the supported palladium-gold catalyst. 16. The method of claim 15, wherein the titanium dioxide support has a total intrusion volume of greater than or equal to 0.35 milliliter of mercury per gram. 17. The method of claim 15, wherein the titanium dioxide support has a total intrusion volume of greater than or equal to 0.40 milliliter of mercury per gram.