Patent ID: 8637719
Filing Date: 2014-01-28
Classification: B01J,C10G

Abstract:
1. A catalyst comprising palladium, at least one alkali metal or alkaline-earth metal, and a porous support in the form of beads or extrudates, comprising at least one refractory oxide that is silica, alumina or silica-alumina, wherein the specific surface area of the porous support is in the range of 50 to 210 m 2 /g, the palladium content in the catalyst is in the range of 0.05% to 2% by weight, at least 80% by weight of the palladium is distributed in a crust at the periphery of the support, the thickness of said crust being in the range of 20 to 200 μm, the metallic dispersion D is in the range of 25% to 70%; the density of the palladium particles in the crust is in the range of 1500 to 4100 particles of palladium per μm 2 , the sum of the quantities of alkali and/or alkaline-earth metals in the catalyst is in the range of 0.05% to 5% by weight and said alkali and/or alkaline-earth metal is distributed homogeneously across the support, with a coefficient R in the range of 0.8 to 1.2, where c is the local concentration of the element, r is the radius of the beads or extrudates and x is the position of the analysis point along the diameter of the grain with respect to the center of that grain.