Method for pretreating and using copper-based catalyst
Method for pretreating the copper-based catalyst having the steps of dehydrating the copper-based catalyst at an elevated temperature, reducing the dehydrated copper-based catalyst with hydrogen, and passivating the activated copper-based catalyst to obtain a catalyst suitable for N-alkylation. The dehydration and reduction steps may be conducted simultaneously.
1. A method for pretreating a copper-based catalyst comprising
dehydrating a copper-based catalyst at an elevated temperature,
reducing the dehydrated copper-based catalyst with hydrogen to obtain an activated copper-based catalyst, and
passivating the activated copper-based catalyst by reacting the activated copper-based catalyst with a ketone and a mixture comprising 4-aminodiphenylamine, said mixture made by a formanilide method, in presence of hydrogen at a temperature of about 100° C. to 180° C. and a hydrogen gas pressure of about 2 MPa to 6 MPa for about 20 to 40 hours, to obtain a passivated copper-based catalyst,
wherein the mixture made by the formanilide method is prepared by
reacting formic acid with aniline to form formanilide,
reacting the formanilide with para-nitrochlorobenzene to form 4-nitrodiphenylamine, and
reducing the 4-nitrodiphenylamine to the 4-aminodiphenylamine, optionally in presence of sodium sulfide as a reduction agent.
2. The method of claim 1 , wherein the copper-based catalyst comprises about 10% to 70% copper oxide.
3. The method of claim 1 , wherein the copper-based catalyst comprises about 30 to 50% copper oxide.
4. The method of claim 1 , wherein the copper-based catalyst comprises a carrier that is ZnO, Al 2 O 3 , SiO 2 , activated carbon, glass fiber net, ceramic ball, layered graphite, natural clay, cerium oxide, or a mixture thereof.
5. The method of claim 1 , wherein the copper-based catalyst is dehydrated at the elevated temperature of more than about 100° C. and under pressure of an inert gas at about 1 MPa to 5 MPa.
6. The method of claim 5 , wherein the copper-based catalyst is dehydrated at about 120° C. to 150° C.
7. The method of claim 1 , wherein time for dehydration is about 4 to 12 hours.
8. The method of claim 1 , wherein the temperature is elevated at about 5° C. to 10° C. per hour during dehydration.
9. The method of claim 1 , wherein the dehydrated copper-based catalyst is reduced with hydrogen in a liquid or gas phase.
10. The method of claim 1 , wherein the dehydrated copper-based catalyst is reduced at a temperature of about 110° C. to 280° C., hydrogen gas is fed at a volume concentration of about 0.1% to 100%, and reaction time is about 40 to 100 hours.
11. The method of claim 1 , wherein the temperature for reduction is elevated at about 1° C. to 15° C. per hour.
12. The method of claim 1 , wherein the copper-based catalyst is dehydrated and reduced simultaneously.
13. The method of claim 1 , wherein molar ratio of the 4-aminodiphenylamine to the ketone is about (1:1) to (1:4).
14. The method for making alkylated derivatives of 4-aminodiphenylamine according to claim 1 , comprising
dehydrating a copper-based catalyst at an elevated temperature,
reducing the dehydrated copper-based catalyst with hydrogen to obtain an activated copper-based catalyst, and
passivating the activated copper-based catalyst by treating the activated copper-based catalyst with a ketone and a mixture comprising 4-aminodiphenylamine, said mixture made by a formanilide method, in presence of hydrogen at a temperature of about 100° C. to 180° C. and hydrogen gas pressure of about 2 MPa to 6 MPa for about 20 to 40 hours, to obtain a passivated copper-based catalyst, and
reacting 4-aminodiphenylamine with a ketone in presence of hydrogen and the passivated copper-based catalyst to obtain alkylated derivatives of 4-aminodiphenylamine,
wherein the mixture made by the formanilide method is prepared by
reacting formic acid with aniline to form formanilide,
reacting the formanilide with para-nitrochlorobenzene to form 4-nitrodiphenylamine, and
reducing the 4-nitrodiphenylamine to the 4-aminodiphenylamine, optionally in presence of sodium sulfide as a reduction agent.
15. The method of claim 14 , wherein the reaction of 4-aminodiphenylamine and the ketone in the presence of hydrogen and the passivated catalyst for making the alkylated derivatives of 4-aminodiphenylamine is conducted at a temperature of about 110° C. to 240° C., a hydrogen pressure of about 2 MPa to 8 MPa.
16. The method of claim 14 , wherein the reaction of 4-aminodiphenylamine and the ketone in the presence of hydrogen and the passivated catalyst for making the alkylated derivatives of 4-aminodiphenylamine is conducted continuously, and a total feed amount of 4-aminodiphenylamine and ketone is about 10 to 25% by weight per hour of the weight of the catalyst.
17. A method for pretreating a copper-based catalyst comprising
dehydrating the copper-based catalyst at an elevated temperature,
reducing the dehydrated copper-based catalyst with hydrogen to obtain an activated copper-based catalyst, and
passivating the activated copper-based catalyst by reacting the activated copper-based catalyst with a compound comprising sulfur or a halogen in a mixture comprising 4-aminodiphenylamine, said mixture made by a nitrobenzene method, and a ketone in presence of hydrogen gas,
wherein the passivation reaction is conducted in the mixture having a molar ratio of the 4-aminodiphenylamine made by the nitrobenzene method to the ketone at about (1:1) to (1:4); reaction temperature is about 100° C. to 180° C.; reaction time is about 20 to 40 hours; pressure of the hydrogen gas is about 2 MPa to 8 MPa, and
wherein the mixture made by the nitrobenzene method is prepared by
reacting aniline with nitrobenzene to make 4-nitrodiphenylamine and 4-nitrosodiphenylamine, and
reducing the 4-nitrodiphenylamine and 4-nitrosodiphenylamine to the 4-aminodiphenylamine.
18. The method of claim 17 , wherein a ratio of the halogen-containing compound to the copper-based catalyst is about 0.05-1 mole halogen per kilogram catalyst.
19. The method of claim 17 , wherein the sulfur-containing compound or the halogen-containing compound is selected from the group consisting of carbon disulfide, hydrogen sulfide, chlorophenylamine, 2-mercaptobenzothiazole, thiophene, and tetramethyl thiuram disulfide.
20. The method of claim 17 , wherein the sulfur-containing compound or the halogen-containing compound is dissolved in an alcohol, ketone, or amine solvent to form the solution for passivating the catalyst.
21. The passivated copper-based catalyst prepared by the method of claim 1 .
22. The passivated copper-based catalyst of claim 21 , comprising metal copper in a reduced form.
23. The method for making alkylated derivatives of 4-aminodiphenylamine according to claim 21 , comprising
reacting 4-aminodiphenylamine with a ketone in presence of hydrogen and the passivated copper-based catalyst to obtain alkylated derivatives of 4-aminodiphenylamine.
24. The method of claim 17 , wherein the copper-based catalyst comprises about 10% to 70% copper oxide.
25. The method of claim 17 , wherein the copper-based catalyst comprises about 30 to 50% copper oxide.
26. The method of claim 17 , wherein the copper-based catalyst comprises a carrier that is ZnO, Al 2 O 3 , SiO 2 , activated carbon, glass fiber net, ceramic ball, layered graphite, natural clay, cerium oxide, or a mixture thereof.
27. The method of claim 17 , wherein the copper-based catalyst is dehydrated at the elevated temperature of more than about 100° C. and under pressure of an inert gas at about 1 MPa to 5 MPa.
28. The method of claim 27 , wherein the copper-based catalyst is dehydrated at about 120° C. to 150° C.
29. The method of claim 17 , wherein time for dehydration is about 4 to 12 hours.
30. The method of claim 17 , wherein the temperature is elevated at about 5° C. to 10° C. per hour during dehydration.
31. The method of claim 17 , wherein the dehydrated copper-based catalyst is reduced with hydrogen in a liquid or gas phase.
32. The method of claim 17 , wherein the dehydrated copper-based catalyst is reduced at a temperature of about 110° C. to 280° C., hydrogen gas is fed at a volume concentration of about 0.1% to 100%, and reaction time is about 40 to 100 hours.
33. The method of claim 17 , wherein the temperature for reduction is elevated at about 1° C. to 15° C. per hour.
34. The method of claim 17 , wherein the copper-based catalyst is dehydrated and reduced simultaneously.
35. The passivated copper-based catalyst prepared by the method of claim 17 .
36. The passivated copper-based catalyst of claim 35 , comprising metal copper in a reduced form.
37. The method for making alkylated derivatives of 4-aminodiphenylamine according to claim 35 , comprising
reacting 4-aminodiphenylamine with a ketone in presence of hydrogen and the passivated copper-based catalyst to obtain alkylated derivatives of 4-aminodiphenylamine.
38. The method for making alkylated derivatives of 4-aminodiphenylamine according to claim 17 , comprising
dehydrating a copper-based catalyst at an elevated temperature,
reducing the dehydrated copper-based catalyst with hydrogen to obtain an activated copper-based catalyst, and
passivating the activated copper-based catalyst by reacting the activated copper-based catalyst with a compound comprising sulfur or a halogen in a mixture comprising 4-aminodiphenylamine, said mixture made by a nitrobenzene method, and a ketone in presence of hydrogen gas, at a temperature of about 100° C. to 180° C. for about 20 to 40 hours, and
reacting 4-aminodiphenylamine with a ketone in presence of hydrogen and the passivated copper-based catalyst to obtain alkylated derivatives of 4-aminodiphenylamine,
wherein the mixture made by the nitrobenzene method is prepared by
reacting aniline with nitrobenzene to make 4-nitrodiphenylamine and 4-nitrosodiphenylamine, and
reducing the 4-nitrodiphenylamine and 4-nitrosodiphenylamine to the 4-aminodiphenylamine.
39. The method of claim 38 , wherein the reaction of 4-aminodiphenylamine and the ketone in the presence of hydrogen and the passivated catalyst for making the alkylated derivatives of 4-aminodiphenylamine is conducted at a temperature of about 110° C. to 240° C., a hydrogen pressure of about 2 MPa to 8 MPa.
40. The method of claim 38 , wherein the reaction of 4-aminodiphenylamine and the ketone in the presence of hydrogen and the passivated catalyst for making the alkylated derivatives of 4-aminodiphenylamine is conducted continuously, and a total feed amount of 4-aminodiphenylamine and ketone is about 10 to 25% by weight per hour of the weight of the catalyst.