Patent ID: 8207327

Claim:
A coated catalyst comprising, as an active metal, ruthenium alone or together with at least one further metal of transition groups IB, VIIB or VIII of the Periodic Table of the Elements (CAS version), applied to a support material consisting of silicon dioxide at least to an extent of 90% by weight and the remaining up to 10% by weight of the support material being selected from the group consisting of MgO, CaO, TiO 2 , ZrO 2 , Fe 2 O 3 , and alkali metal oxide, or a mixture thereof, wherein the amount of the active metal is <1% by weight based on the total weight of the catalyst, and at least 60% by weight of the active metal is present in the coating of the catalyst up to a penetration depth of 200 μm, determined by SEM-EPMA (EDXS), wherein the catalyst is prepared by impregnating the support material once or more than once with a solution of ruthenium(III) acetate alone or together with a solution of at least one further salt of metals of transition groups IB, VIIB or VIII of the Periodic Table of the Elements (CAS version), drying and reduction, the solution of the at least one further salt of metals of transition groups IB, VIIB or VIII of the Periodic Table of the Elements being applicable in one or more impregnation steps together with the solution of ruthenium(III) acetate or in one or more impregnation steps separately from the solution of ruthenium(III) acetate.