Post-gilding of PD-AU-coated shell catalysts

A process for producing an eggshell catalyst, comprising the steps of:

• (a) subjecting a bed of a catalyst support body to a circulating motion;
• (b) contacting an atomized aqueous solution comprising a Pd-containing precursor compound and an Au-containing precursor compound with the bed of the catalyst support body subjected to the circulating motion by spraying;
• (c) contacting an atomized aqueous solution comprising an Au-containing precursor compound with the catalyst support body obtained after step (b);
• and
• (d) metal reduction by subjecting the catalyst support body obtained in step (c) to a thermal treatment in a nonoxidizing atmosphere and
• wherein the Au-containing precursor compounds in steps (b) and (c) are, independently, compounds selected from the group consisting of hydroxidic metalate compounds.