Catalyst and process for hydrogenating organic compounds
The invention relates to a catalyst and to a process for hydrogenating organic compounds. In particular, the invention is directed to a process and catalyst for hydrogenating organic compounds with hydrogen. The organic compounds are subjected to hydrogenation in the presence of a catalyst comprising nitrogen-doped carbon nanotubes as a catalytically active component, wherein the proportion of nitrogen in the nanotubes is in the range of from about 0.05 to 20 wt. %.
1. A process for hydrogenating organic compounds by means of hydrogen comprising hydrogenating the organic compound in the presence of a catalyst, said catalyst comprising nitrogen-doped carbon nanotubes as catalytically active component, wherein said nanotubes are present as an agglomerate with Co—Mn—Al—Mg mixed oxide catalyst, and the proportion of nitrogen in the nitrogen-doped carbon nanotubes is in the range from 0.05 to 20% by weight in graphitic layers and the nitrogen is present at least partly in a pyridinic arrangement, wherein the organic compound is a nitroaromatic substrate.
2. The process as claimed in claim 1 wherein the organic compound is present in a liquid phase and the hydrogen in the present in gaseous form.
3. The process as claimed in claim 2 wherein the organic compound is present in a liquid solvent.
4. The process as claimed in claim 3 wherein the solvent is an organic solvent which does not comprise any hydrogenation-active functional group or is a mixture of such organic solvents.
5. The process as claimed in claim 2 wherein the process is carried out at temperatures in the range from 20° C. to 350° C.
6. The process as claimed in claim 1 wherein the organic compound and the hydrogen are present in gaseous form.
7. The process as claimed in claim 1 wherein the process is carried out at temperatures of from 120 to 750° C.
8. The process as claimed in claim 1 wherein the process is carried out in a plurality of stages reaction zones connected in series.
9. The process as claimed in claim 1 wherein the catalyst contains at least 50% by weight of nitrogen-doped carbon nanotubes.
10. The process as claimed in claim 1 wherein the catalyst is present as a fixed bed.
11. The process as claimed in claim 10 wherein the fixed bed is present in the form of a structured bed in which the catalyst activity increases in the main flow direction in the reaction zone.
12. The process as claimed in claim 8 wherein the process is carried out in 2-3 reaction zones.
13. The process as claimed in claim 9 wherein the catalyst contains at least 95% by weight of nitrogen-doped carbon nanotubes.
14. The process as claimed in claim 7 wherein the process is carried out at temperatures of from 200 to 600° C.
15. The process as claimed in claim 1 wherein the organic compound is nitrobenzene.