Fixed catalyst bed comprising metal foam bodies
The present invention relates to a fixed bed of catalytically active metal foam bodies having a volume of not more than 500 mL which consist to an extent of at least 95 wt % of metals. The fixed bed is used for catalytic reactions in a three-phase reaction mixture.
1. A fixed bed comprising catalytically active metal foam bodies for catalytic reaction of at least one reactant component in a liquid phase and at least one gaseous component, wherein the catalytically active metal foam bodies have a volume of not more than 500 millilitres, comprise at least 95 wt % of metals and are arranged as bulk goods in a packed bed and wherein the catalytically active metal foam bodies have a BET surface area of 1 to 200 m 2 /g and an oxygen content of not more than 7500 ppm.
2. The fixed bed of claim 1 , wherein the catalytically active metal foam bodies comprise one or more metals selected from the group consisting of: nickel, cobalt, iron, silver, platinum, chromium, molybdenum and tungsten.
3. The fixed bed of claim 2 , wherein the catalytically active metal foam bodies further comprise up to 25 wt % of Al.
4. The fixed bed of claim 1 , wherein the catalytically active metal foam bodies are present in the fixed bed as a loose fill material, wherein a volume of 1 L of this loose fill material has a weight of not more than 0.8 kg.
5. The fixed bed of claim 1 , wherein the catalytically active metal foam bodies are in the form of cylindrical, ring-shaped, cuboid, parallelepipedal or cubic bodies.
6. The fixed bed of claim 5 , wherein the catalytically active metal foam bodies have a cylindrical shape.
7. The fixed bed of claim 6 , wherein the cylindrically shaped catalytically active metal foam bodies are corrugated.
8. The fixed bed of claim 1 , wherein the catalytically active metal foam bodies have macroscopic pores having a size in the range from 100 to 5000 μm.
9. A process for catalytic reaction of at least one reactant component in a liquid phase and at least one gaseous component wherein said process is carried out using the fixed bed of claim 1 .
10. The process of claim 9 , wherein the process is performed as a continuous operation in a reactor having a total volume of at least 0.5 m 3 .
11. The process of claim 9 , wherein the catalytic reaction is a hydrogenation, wherein hydrogen is the gaseous component and the reactant component in the liquid phase comprises at least one unsaturated C—C bond and/or at least one functional group.
12. The process of claim 9 , wherein the catalytic reaction is a hydrogenation of at least one substance selected from the group consisting of: alkenes, alkynes, unsaturated alcohols, aromatic compounds, organic nitro and nitroso compounds, organic isocyanates, organic cyanide compounds, aldehydes and ketones; and wherein hydrogen is employed as the gaseous component.
13. The process of claim 9 , wherein the catalytic reaction is the hydrogenation of a sugar.
14. The process of claim 9 , wherein the catalytic reaction is a dehydrogenation of alcohols to produce aldehydes and/or ketones or a reductive amination of aldehydes and/or ketones.
15. The process of claim 9 , wherein the catalytic reaction is a synthesis of fatty amines or a reductive alkylation of organic compounds.
16. The fixed bed of claim 2 , wherein the catalytically active metal foam bodies are present in the fixed bed as a loose fill material, wherein a volume of 1 L of this loose fill material has a weight of not more than 0.8 kg.
17. The fixed bed of claim 16 , wherein the catalytically active metal foam bodies have macroscopic pores having a size in the range from 100 to 5000 μm.