Abstract: The present invention relates to a process for separating at least one metal compound and/or a component thereof from a mixture, said process comprising contacting the said mixture with a heteropoly acid or heteropoly acid anion, thereby producing a precipitate comprising the heteropoly acid or heteropoly acid anion and the metal compound and/or a component thereof. The present invention further relates to a process for the purification of a mixture containing at least one metal compound, said process comprising contacting the said mixture with a heteropoly acid or heteropoly acid anion, thereby producing a precipitate that is substantially insoluble in the said reaction mixture and recovering the reaction mixture.

Abstract: The present invention relates to a catalyst nickel, silica, alumina and magnesium, wherein the nickel to magnesium atomic ratio is 5-75. In particular the present invention relates to a catalyst comprising nickel, silica, alumina and magnesium, wherein the nickel to silicium atomic ratio (Ni/Si) is 2 to 30 the nickel to aluminum atomic ratio (Ni/Al) is 9 to 40 and the nickel to magnesium atomic ratio (Ni/Mg) is 5-75. The invention further relates to a method for preparing such a catalyst. The invention further relates to a process for hydrogenating unsaturated organic compounds.