Process for the reduction of carbon monoxide and carbonyl sulfide emissions

A freeze-dried, heat treated composition of matter, comprising Au, Rh, Ru, Cr, cerium oxide and lanthanum oxide, made by a process comprising the steps of:

• (i) dissolving precursor salts selected from the group consisting of Au, Rh, Ru, Ce, Cr and La in a solvent to form a solution or colloid;
• or, optionally, combining metal or metal oxide colloids, wherein the metal is selected from the group consisting of Au, Rh, Ru, Ce, Cr and La, to form a colloid mixture;
• or a combination thereof;
• (ii) freezing the product of step (i) to form a frozen solid;
• (iii) transferring the frozen solid to a freeze drying chamber maintained at a temperature ranging from about 0° C. to about −40° C. with a vacuum of from about 0.3 Pa to about 1.3 Pa until freeze-drying is complete;
• and
• (iv) heating the solid in air at a temperature ranging from about 250° C. to about 600° C. for a time sufficient to decompose the precursors.

A process for making a freeze-dried, heat treated composition of matter comprising Au, Rh, Ru, Cr, cerium oxide and lanthanum oxide, comprising the steps of:

• (i) dissolving precursor salts selected from the group consisting of Au, Rh, Ru, Ce, Cr and La in a solvent to form a solution or colloid;
• or, optionally, combining metal or metal oxide colloids, wherein the metal is selected from the group consisting of Au, Rh, Ru, Ce, Cr and La, to form a colloid mixture;
• or a combination thereof;
• (ii) freezing the product of step (i) to form a frozen solid;
• (iii) transferring the frozen solid to a freeze drying chamber maintained at a temperature ranging from about 0° C. to −40° C. with a vacuum of from about 0.3 Pa to about 1.3 Pa until freeze-drying is complete;
• and
• (iv) heating the solid in air at a temperature ranging from about 250° C. to about 600° C. for a time sufficient to decompose the precursors.