Hydrogenation catalyst and hydrogenation process

Abstract

A supported hydrogenation catalyst comprising (1) Pd or a Group 8 metal comprising Pd and one other Group 8 metal, preferably a Group 8 metal selected from Pt, Ir, Ru, Co or Ni, and (2) at least two metals selected from Ag, Zn or Bi, preferably Ag and at least one of Zn or Bi. Optionally the catalyst may contain K. The catalyst is supported on a porous support such as a silica, alumina, silica-alumina or carbon. The preferred supports have an average pre diameter of 180 Å with no pores smaller than 35 Å, total pore volume larger than 0.65 cc/g and preferably less than about 100 m 2 /g BET surface area. The catalysts are useful for the hydrogenation of unsaturated hydrocarbons such as acetylenes and diolefins in various mixed olefin streams.

1 . A supported catalyst for the selective hydrogenation of unsaturated compounds comprising a catalyst comprising (1) Pd or a Group 8 metal comprising Pd and one other Group 8 metal component and (2) at least two metals selected from the group consisting of Ag, Zn and Bi supported on shaped transition alumina having an apparent bulk density of between 0.7-0.8 g/cm 3  and having mixed crystalline forms of α, κ, θ, δ, ρ, η, γ, and χ, which is highly porous having average pore diameter larger than about 180 Å, no pores narrower than 35 Å, total pore volume larger than about 0.65 cc/g, and BET surface area of 20 to 70 m 2 /g.  
     
     
         2 . The catalyst according to  claim 1  comprising a group 8 metal component comprising Pd and one other Group 8 metal.  
     
     
         3 . The catalyst according to  claim 2  wherein said Group 8 metal is selected from the group consisting of Pt, Ir, Ru, Co and Ni.  
     
     
         4 . The catalyst according to  claim 1  comprising Ag and at least one of Zn or Bi.  
     
     
         5 . (canceled)  
     
     
         6 . The catalyst according to  claim 1  comprising K.  
     
     
         7 . The catalyst according to  claim 1  wherein Pd is in the range of 0.005 to 1% by weight; Ni is in the range of 0.0 to 15% by weight; Ag is in the range of 0.002 to 20% by weight; Zn is in the range of 0 to 5% by weight and Bi is in the range of 0 to 5% by weight.  
     
     
         8 . The catalyst according to  claim 1  wherein Pd is in the range of from 0.01% to 0.3% by weight; Ni is in the range of from 0 to 10% by weight; Ag is in the range of 0.005 to 5% by weight; Zn is in the range of 0.002 to 1% by weight and Bi is in the range of 0.01 to 3% by weight.  
     
     
         9 . The catalyst according to  claim 6  wherein the content of K is less that 0.5% by weight.  
     
     
         10 .- 20 . (canceled)