A catalyst comprising gold, palladium, and a porous support, in the form of at least one grain, in which: the gold content in the catalyst is in the range 0.5% to 3% by weight with respect to the total weight of catalyst; the mean particle size of the gold, estimated by transmission electron microscopy (TEM), is in the range 0.5 nm to 5 nm; the gold is distributed homogeneously in the porous support; at least 80% by weight of the palladium is distributed in an eggshell at the periphery of the porous support; the gold/palladium molar ratio is more than 2.

A catalyst comprising gold, palladium, and a porous support, in the form of at least one grain, in which: the gold content in the catalyst is in the range 0.5% to 3% by weight with respect to the total weight of catalyst; the mean particle size of the gold, estimated by transmission electron microscopy (TEM), is in the range 0.5 nm to 5 nm; the gold is distributed homogeneously in the porous support; at least 80% by weight of the palladium is distributed in an eggshell at the periphery of the porous support; the gold/palladium molar ratio is more than 2.

A catalyst for the total hydrogenation of an olefin-containing hydrocarbon stream can be made. The catalyst has a support material and platinum as a catalytically active metal. A process for the total hydrogenation of an olefin-containing hydrocarbon stream in at least one reactor with addition of hydrogen and using the catalyst can be performed.

Producing C5 olefins from steam cracker C5 feeds may include reacting a mixed hydrocarbon stream comprising cyclopentadiene, C5 olefins, and C6+ hydrocarbons in a dimerization reactor where cyclopentadiene is dimerized to dicyclopentadiene. The dimerization reactor effluent may be separated into a fraction comprising the C6+ hydrocarbons and dicyclopentadiene and a second fraction comprising C5 olefins and C5 dienes. The second fraction, a saturated hydrocarbon diluent stream, and hydrogen may be fed to a catalytic distillation reactor system for concurrently separating linear C5 olefins from saturated hydrocarbon diluent, cyclic C5 olefins, and C5 dienes contained in the second fraction and selectively hydrogenating C5 dienes. An overhead distillate including the linear C5 olefins and a bottoms product including cyclic C5 olefins are recovered from the catalytic distillation reactor system. Other aspects of the C5 olefin systems and processes, including catalyst configurations and control schemes, are also described.

Producing C5 olefins from steam cracker C5 reeds may include reacting a mixed hydrocarbon stream comprising cyclopentadiene, C5 olefins, and C6+ hydrocarbons in a dimerization reactor where cyclopentadiene is dimerized to dicyclopentadiene. The dimerization reactor effluent may be separated into a traction comprising the C6+ hydrocarbons and dicyclopentadiene and a second fraction comprising C5 olefins and C5 dienes. The second fraction, a saturated hydrocarbon diluent stream, and hydrogen may be fed to a catalytic distillation reactor system for concurrently separating linear C5 olefins from saturated hydrocarbon diluent, cyclic C5 olefins, and C5 dienes contained in the second fraction and selectively hydrogenating C5 dienes. An overhead distillate including the linear C5 olefins and a bottoms product including cyclic C5 olefins are recovered from the catalytic distillation reactor system. Other aspects of the C5 olefin systems and processes, including catalyst configurations and control schemes, are also described.

A catalyst comprises an active phase constituted by palladium, and a porous support comprising at least one refractory oxide selected from the group constituted by silica, alumina and silica-alumina, in which: the palladium content in the catalyst is in the range 0.0025% to 1% by weight with respect to the total weight of catalyst; at least 80% by weight of the palladium is distributed in a crust at the periphery of the porous support, the thickness of said crust being in the range 25 to 500 m; the specific surface area of the porous support is in the range 1 to 50 m.sup.2/g; the metallic dispersion D of the palladium is less than 20%.

The present invention is in the field of catalysis. More particularly, the present invention is directed to supported precious metal, preferably palladium and/or gold metal catalysts, having a high degree of dispersion and a high degree of edge-coating. The present invention is further directed to a process for producing these catalysts, as well as to the use of these catalysts in chemical reactions.

A catalyst comprising gold and a porous support containing at least one refractory oxide, in which the gold content is in the range 0.01% to 5% by weight with respect to the total weight of catalyst, and in which the particles of gold are distributed homogeneously through said porous support and have a dimension, measured by transmission electron microscopy, in the range 0.5 to 5 nm.

A catalyst comprising gold and a porous support containing at least one refractory oxide, in which the gold content is in the range 0.01% to 5% by weight with respect to the total weight of catalyst, and in which the particles of gold are distributed homogeneously through said porous support and have a dimension, measured by transmission electron microscopy, in the range 0.5 to 5 nm.

A catalyst comprising gold, palladium, and a porous support, in the form of at least one grain, in which: the gold content in the catalyst is in the range 0.5% to 3% by weight with respect to the total weight of catalyst; the mean particle size of the gold, estimated by transmission electron microscopy (TEM), is in the range 0.5 nm to 5 nm; the gold is distributed homogeneously in said porous support; at least 80% by weight of the palladium is distributed in an eggshell at the periphery of said porous support; the gold/palladium molar ratio is more than 2.