Shell impregnated catalyst and process for producing a shell impregnated catalyst body

Abstract

The present application relates to a process for producing a catalyst,said process comprising the steps of: providing a carrier and following modifying said carrier by a first impregnation with at least one alkaline earth metal in a first metal precursor solution. The first metal precursor is decomposed to form at least one metal oxide or metal hydroxide thereby obtaining a modified carrier and a second impregnation is carried out by incipient wetness by a second precursor solution comprising at least one metal Me in a second solution. Finally the second precursor is decomposed thereby obtaining a catalyst body having an enrichment of the at least one metal Me in the outer shell of the catalyst body, said at least one metal being present in a concentration having either as an egg-shell profile or a hammock profile.

1 . A process for producing a catalyst, said process comprising the steps of:
 providing a carrier   modifying said carrier by a first impregnation with at least one alkaline earth metal in a first metal precursor solution   decomposing the first metal precursor to form at least one metal oxide or metal hydroxide thereby obtaining a modified carrier   carrying out a second impregnation by incipient wetness by a second precursor solution comprising at least one metal Me in a second solution   decomposing the second precursor thereby obtaining a catalyst body having an enrichment of the at least one metal Me in the outer shell of the catalyst body, said at least one metal being present in a concentration having either an egg-shell profile and/or a hammock profile.   
     
     
         2 . A process according to  claim 1  wherein the carrier is alumina spinel and/or calcium aluminate. 
     
     
         3 . Process according to  claim 1 , wherein carrier has a pore volume 200-400 ml/kg, and/or BET surface area 2-50 m 2 /g. 
     
     
         4 . Process according to  claim 1 , comprising repeating the second impregnation one or more times. 
     
     
         5 . A process according to  claim 1 , wherein the first precursor solution is a nitrate, carbonate or hydroxide of the alkaline earth metals. 
     
     
         6 . A process according to  claim 1 , wherein the first decomposition is carried out at 350-550° C. 
     
     
         7 . A process according to  claim 1 , wherein the alkaline earth metal is taken from the group of Mg, Ca, Sr and/or Ba. 
     
     
         8 . A process according to  claim 1 , wherein the alkaline, earth metal concentration is 0.5-10 wt % after impregnation. 
     
     
         9 . A process according to  claim 1 , wherein the second solvent is a metal Me precursor in the form of nitrate, acetate, citrate, EDTA and/or EDA. 
     
     
         10 . A process according to  claim 1 , wherein the metal Me is Ni, Ru, Rh, Ir, Pd and/or Pt. 
     
     
         11 . A process according to  claim 1 , wherein the metal Me is Ni, Ru and/or Rh. 
     
     
         12 . A process according to  claim 1 , wherein the impregnated carrier is dried between the second impregnation and the second decomposition. 
     
     
         13 . A process according to  claim 1 , wherein the second decomposition is carried out at 350-600° C. 
     
     
         14 . A catalyst produced by the process according to  claim 1 . 
     
     
         15 . A catalyst comprising a core section and a shell section, wherein
 the core section comprises a carrier, preferably from alumina spinel and/or calcium aluminates, and at least one alkaline earth metal oxide and/or alkaline earth metal hydroxide   the shell section comprises the carrier, preferably alumina spinel and/or calcium aluminates, and at least one alkaline earth metal oxide and/or alkaline earth metal hydroxide and at least one metal Me.   
     
     
         16 . A catalyst according to  claim 15 , comprising a core section and a shell section, wherein
 the carrier is alumina spinel and/or calcium aluminates and/or where the alkaline earth metal oxide and/or alkaline earth metal hydroxide is MgO, Mg(OH) 2 , CaO and/or Ca(OH) 2 , and   the shell section comprises alumina spinel and/or calcium aluminates and MgO, Mg(OH) 2 , CaO and/or Ca(OH) 2  and at least one metal Me.   
     
     
         17 . Catalyst according to  claim 15 , wherein the metal Me is Ni, Ru and/or Rh. 
     
     
         18 . Catalyst according to  claim 15 , wherein the concentration of alkaline earth metal oxide and/or alkaline earth metal hydroxide such as MgO, Mg(OH) 2 , CaO and/or Ca(OH) 2  in the core section is 0.5-10 wt %. 
     
     
         19 . Catalyst according to  claim 15 , wherein the concentration of Me in the shell is <20 wt % wt %. 
     
     
         20 . Catalyst according to  claim 15 , wherein the pore volume is 200-500 ml/kg and/or BET surface area is 2-50 m 2 /g. 
     
     
         21 . Catalyst according to  claim 15 , wherein the shell thickness is 10-1000 μm. 
     
     
         22 . Catalyst according to  claim 15 , wherein the shell thickness is 40-500 μm. 
     
     
         23 . Catalyst according to  claim 15 , wherein the shell thickness is 50-300 μm. 
     
     
         24 . Catalyst according to  claim 15 , having a radius of 5-100 mm. 
     
     
         25 . Catalyst according to  claim 15 , having a spherical, cylindrical, or other shape. 
     
     
         26 . Catalyst according to  claim 15 , having a body with one or more indentation and/or through-going holes. 
     
     
         27 . A catalyst obtained according to the process of  claim 1 , the catalyst comprising a core section and a shell section, wherein
 the core section comprises a carrier from alumina spinel and/or calcium aluminates, and at least one alkaline earth metal oxide and/or alkaline earth metal hydroxide,   the shell section comprises the carrier, preferably alumina spinel and/or calcium aluminates, and at least one alkaline earth metal oxide and/or alkaline earth metal hydroxide and at least one metal Me.   
     
     
         28 . Process for producing a syngas, said process comprising at least one reforming step of contacting a feed stream with a catalyst according to  claim 1  and wherein the reforming step comprises steam reforming, primary reforming, secondary reforming auto thermal reforming and/or partial oxidation. 
     
     
         29 . Use of a catalyst according to  claim 1 , for steam reforming, primary reforming, secondary reforming, autothermal reforming and/or partial oxidation. 
     
     
         30 . A reformer comprising a catalyst according to  claim 1 .