Method for direct amination of hydrocarbons to form amino hydrocarbons with the electrochemical separation of hydrocarbon

Patent metadata

Field	Value
Publication number	US-9061961-B2
Application number	US-201013383321-A
Country	US
Kind code	B2
Filing date	Jul 8, 2010
Priority date	Jul 10, 2009
Publication date	Jun 23, 2015
Grant date	Jun 23, 2015

Abstract

Process for the direct amination of hydrocarbons to aminohydrocarbons, which comprises the steps:
a) reaction of a feed stream E comprising at least one hydrocarbon and at least one aminating reagent to form a reaction mixture R comprising aminohydrocarbons and hydrogen and b) electrochemical separation of at least part of the hydrogen formed in the reaction from the reaction mixture R by means of a gastight membrane-electrode assembly having at least one selectively proton-conducting membrane and at least one electrode catalyst on each side of the membrane, where at least part of the hydrogen is oxidized to protons over the anode catalyst on the retentate side of the membrane and the protons are, after passing through the membrane,
b1) reduced to hydrogen and/or b2) reacted with oxygen from an oxygen-comprising stream O which is brought into contact with the permeate side of the membrane to form water over the cathode catalyst on the permeate side.

First claim

The invention claimed is:

1. A process for direct amination of a hydrocarbon to an aminohydrocarbon, the process comprising:
a) reacting a feed stream E comprising a hydrocarbon and an aminating reagent to obtain a reaction mixture R comprising an aminohydrocarbon and hydrogen and
b) electrochemically separating at least part of the hydrogen from the reaction mixture R with a gastight membrane-electrode assembly, leaving a product stream P,
wherein the membrane-electrode assembly comprises a selectively proton-conducting membrane having a retentate side and a permeate side, an anode catalyst on the retentate side of the membrane, and a cathode catalyst on the permeate side of the membrane,
electrochemically separating at least part of the hydrogen b) comprises oxidizing at least part of the hydrogen to protons over the anode catalyst and passing the protons through the membrane,
electrochemically separating at least part of the hydrogen b) further comprises either reducing the protons over the cathode catalyst to obtain hydrogen, or reacting the protons with oxygen from an oxygen-comprising stream O over the cathode catalyst to obtain water.

2. The process of claim 1 , further comprising separating the aminohydrocarbon from the reaction mixture R before electrochemically separating at least part of the hydrogen.

3. The process of claim 1 , further comprising separating the aminohydrocarbon from the product stream P.

4. The process of claim 1 , further comprising:
removing the aminohydrocarbon from the reaction mixture R, removing the aminohydrocarbon from the product stream P, or both, and then
recirculating the product stream P to a direct amination reaction.

5. The process of claim 1 , wherein separating hydrogen from the reaction mixture R comprises separating at least 30% of the hydrogen out from the reaction mixture R.

6. The process of claim 1 , wherein a temperature of separating hydrogen from the reaction mixture R is from 20 to 800° C.

7. The process of claim 1 ,
wherein electrochemically separating at least part of the hydrogen b) comprises reducing the protons to hydrogen over the cathode catalyst, and
a potential of electrochemically separating at least part of the hydrogen b) is from 0.05 to 2000 mV.

8. The process claim 1 ,
wherein electrochemically separating at least part of the hydrogen b) comprises reacting the protons with oxygen from an oxygen-comprising stream O over the cathode catalyst to obtain water, and
the oxygen-comprising stream O comprises at least 15 mol % of oxygen.

9. The process of claim 1 , wherein each electrode of the membrane-electrode assembly is a metallic foil.

10. The process of claim 1 ,
wherein electrochemically separating at least part of the hydrogen b) comprises reacting the protons with oxygen from an oxygen-comprising stream O over the cathode catalyst to obtain water and heat, and
at least part of the heat is fed to a reaction zone where feed stream E reacts to produce reaction mixture R.

11. The process of claim 1 , wherein each electrode of the membrane-electrode assembly is a gas diffusion electrode.

12. The process of claim 1 ,
wherein the selectively proton-conducting membrane comprises at least one membrane selected from the group consisting of a ceramic membrane and a polymer membrane.

13. The process of claim 1 ,
wherein the hydrocarbon comprises benzene, toluene, methane, or a mixture thereof, and
the aminohydrocarbon comprises aniline, toluenediamine, methylamine, or a mixture thereof.

14. A process for direct amination of a hydrocarbon to an aminohydrocarbon, the process comprising:
a) reacting a feed stream E comprising a hydrocarbon and an aminating reagent to obtain a reaction mixture R comprising an aminohydrocarbon and hydrogen and
b) electrochemically separating at least part of the hydrogen from the reaction mixture R with a gastight membrane-electrode assembly,
wherein the membrane-electrode assembly comprises a selectively proton-conducting membrane having a retentate side and a permeate side, an anode catalyst on the retentate side of the membrane, and a cathode catalyst on the permeate side of the membrane,
electrochemically separating at least part of the hydrogen b) comprises oxidizing at least part of the hydrogen to protons over the anode catalyst and passing the protons through the membrane,
electrochemically separating at least part of the hydrogen b) further comprises both reducing the protons over the cathode catalyst to obtain hydrogen and reacting the protons with oxygen from an oxygen-comprising stream O over the cathode catalyst to obtain water.

15. The process of claim 14 , further comprising separating the aminohydrocarbon from the reaction mixture R before electrochemically separating at least part of the hydrogen.

16. The process of claim 14 , further comprising separating the aminohydrocarbon from the product stream P.

17. The process of claim 14 , further comprising:
removing the aminohydrocarbon from the reaction mixture R, removing the aminohydrocarbon from the product stream P, or both, and then
recirculating the product stream P to a direct amination reaction.

18. The process of claim 14 , wherein separating hydrogen from the reaction mixture R comprises separating at least 30% of the hydrogen out from the reaction mixture R.

19. The process of claim 14 , wherein reducing the protons over the cathode catalyst to obtain hydrogen comprises reducing the protons with the water obtained from reacting the protons with oxygen.

20. The process of claim 5 , wherein separating hydrogen from the reaction mixture R comprises separating at least 50% of the hydrogen out from the reaction mixture R.

Assignees

• Kubanek Petr
• Panchenko Alexander
• Fischer Andreas
• Heidemann Thomas
• Basf Se

Inventors

• Kubanek Petr
• Panchenko Alexander
• Fischer Andreas
• Heidemann Thomas

Classifications

• C07C209/02 Primary

  by substitution of hydrogen atoms by amino groups · CPC title

• C25B3/00

  Electrolytic production of organic compounds · CPC title

• Y02P20/582

  Recycling of unreacted starting or intermediate materials · CPC title

• C25B3/09

  Nitrogen containing compounds · CPC title

• C07C211/46

  Aniline · CPC title