Method for forming gold-containing catalyst with porous structure

A method for forming a gold-containing catalyst with porous structure, the method comprising:

• producing a starting alloy by melting together gold and at least one less noble metal that is selected from the group consisting of silver, copper, rhodium, palladium, and platinum, wherein the starting alloy consists essentially of the gold and the at least one less noble metal, wherein the ratio of gold to the less noble metal(s) in the starting alloy is in the range from 45 atom %:55 atom % to 10 atom %:90 atom %;
• shaping the starting alloy into a desired shape;
• annealing the shaped starting alloy after all shaping is completed;
• dealloying the shaped starting alloy to form a porous structure, wherein the dealloying comprises at least partially removing the at least one less noble metal by dissolving at least some of the at least one less noble metal out of the starting alloy, wherein the ratio of gold to the at least one less noble metal in the porous structure is in the range from 100 atom %:0 atom % to 95 atom %:5 atom %, determined using AAS, wherein the porous structure after the dealloying does not contain a support material;
• and
• activating the porous structure at a temperature of 40° C. to 80° C. in a gaseous atmosphere comprising oxygen and carbon monoxide.

A method for forming a gold-containing catalyst with porous structure, the method comprising:

• producing a starting alloy that consists of gold and at least one less noble metal that is selected from the group consisting of silver, copper, rhodium, palladium, and platinum, wherein a ratio of gold to the less noble metal(s) in the starting alloy is in the range from 45 atom %:55 atom % to 10 atom %:90 atom %, wherein producing the starting alloy comprises melting together the gold and the at least one less noble metal;
• annealing the starting alloy;
• dealloying the starting alloy to form a dealloyed porous structure, wherein the dealloying comprises at least partially removing the at least one less noble metal by dissolving at least some of the at least one less noble metal out of the starting alloy, wherein the dealloyed porous structure consists of gold and the at least one less noble metal having a ratio of gold to the at least one less noble metal in a range from 100 atom %:0 atom % to 95 atom %:5 atom %, determined using AAS, wherein the dealloyed porous structure does not contain a support material, wherein the dealloyed porous structure has pores with diameters between about 30 to 100 nm and a surface area in the range of 2 to 4 m2/g;
• activating the dealloyed porous structure at a temperature of between about 40° C. in a gaseous atmosphere containing oxygen and carbon monoxide,
• wherein the activated dealloyed porous structure and
• crushing the activated dealloyed porous structure.