Method for producing hollow fiber carbon membrane and separation membrane module

Patent metadata

Field	Value
Publication number	US-10456751-B2
Application number	US-201615562150-A
Country	US
Kind code	B2
Filing date	Mar 2, 2016
Priority date	Mar 27, 2015
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

An object of the present invention is to provide a method capable of easily controlling the permeation rate and the selectivity of gas molecules, in a hollow fiber carbon membrane which can be used as a gas separation membrane. The present invention provides a method of producing a hollow fiber carbon membrane, the method including: a preparation step of preparing a precursor made of an organic polymer compound in the form of a hollow fiber; a preheating step of heating the precursor to a temperature of 150° C. to 400° C. in an atmosphere containing an oxygen gas; and a carbonization step of heating the precursor which has been subjected to the preheating step to a temperature of 450° C. to 850° C., thereby carbonizing the precursor; wherein the carbonization step includes heating the precursor in the presence of a hydrocarbon gas which may contain a nitrogen atom and which has from 1 to 8 carbon atoms. This method allows for easily controlling the permeation rate and the selectivity of gas molecules, in the resulting hollow fiber carbon membrane.

First claim

The invention claimed is:

1. A method of producing a hollow fiber carbon membrane, the method comprising:
a preparation step of preparing a precursor made of an organic polymer compound in the form of a hollow fiber;
a preheating step of heating the precursor to a temperature of 150° C. to 400° C. in an atmosphere containing an oxygen gas; and
a carbonization step of heating the precursor which has been subjected to the preheating step to a temperature of 450° C. to 850° C., thereby carbonizing the precursor;
wherein the carbonization step comprises heating the precursor in the presence of a hydrocarbon gas which may contain a nitrogen atom and which has from 1 to 8 carbon atoms, and the hydrocarbon gas is supplied from an external source.

2. The method of producing a hollow fiber carbon membrane according to claim 1 , wherein the hydrocarbon gas is a hydrocarbon containing a carbon-carbon unsaturated bond.

3. The method of producing a hollow fiber carbon membrane according to claim 1 , wherein the organic polymer compound comprises at least one selected from the group consisting of polyphenylene oxide, and a polyphenylene oxide derivative containing structures represented by the following formulae (a) and (b):

wherein in the formula (b), each R independently represents a hydrogen atom, —SO 3 H, or —SO 3 NH 4 , with the proviso that the Rs are not simultaneously hydrogen atoms.

4. A separation membrane module comprising a hollow fiber carbon membrane produced by the method of producing a hollow fiber carbon membrane according to claim 1 .

5. The method of producing a hollow fiber carbon membrane according to claim 2 , wherein the organic polymer compound comprises at least one selected from the group consisting of polyphenylene oxide, and a polyphenylene oxide derivative containing structures represented by the following formulae (a) and (b):

wherein in the formula (b), each R independently represents a hydrogen atom, —SO 3 H, or —SO 3 NH 4 , with the proviso that the Rs are not simultaneously hydrogen atoms.

6. A separation membrane module comprising a hollow fiber carbon membrane produced by the method of producing a hollow fiber carbon membrane according to claim 2 .

7. A separation membrane module comprising a hollow fiber carbon membrane produced by the method of producing a hollow fiber carbon membrane according to claim 3 .

8. A separation membrane module comprising a hollow fiber carbon membrane produced by the method of producing a hollow fiber carbon membrane according to claim 5 .

9. The method of producing a hollow fiber carbon membrane according to claim 1 , wherein the carbonization step further comprises supplying an inert gas and the hydrocarbon gas simultaneously, and the concentration of the hydrocarbon gas (volume flow rate of hydrocarbon gas/volume flow rate of inert gas×100[% by volume]) is 5% by volume or more, and 50% by volume or less.

10. The method of producing a hollow fiber carbon membrane according to claim 1 , further comprising elevating a temperature within a reactor while supplying an inert gas in the absence of the hydrocarbon gas before starting the carbonization step.

11. The method of producing a hollow fiber carbon membrane according to claim 1 , wherein the hydrocarbon gas has from 1 to 4 carbon atoms.

12. The method of producing a hollow fiber carbon membrane according to claim 2 , wherein the carbonization step further comprises supplying an inert gas and the hydrocarbon gas simultaneously, and the concentration of the hydrocarbon gas (volume flow rate of hydrocarbon gas/volume flow rate of inert gas×100[% by volume]) is 5% by volume or more, and 50% by volume or less.

13. The method of producing a hollow fiber carbon membrane according to claim 2 , further comprising elevating a temperature within a reactor while supplying an inert gas in the absence of the hydrocarbon gas before starting the carbonization step.

14. The method of producing a hollow fiber carbon membrane according to claim 2 , wherein the hydrocarbon gas has from 1 to 4 carbon atoms.

15. The method of producing a hollow fiber carbon membrane according to claim 3 , wherein the carbonization step further comprises supplying an inert gas and the hydrocarbon gas simultaneously, and the concentration of the hydrocarbon gas (volume flow rate of hydrocarbon gas/volume flow rate of inert gas×100[% by volume]) is 5% by volume or more, and 50% by volume or less.

16. The method of producing a hollow fiber carbon membrane according to claim 3 , further comprising elevating a temperature within a reactor while supplying an inert gas in the absence of the hydrocarbon gas before starting the carbonization step.

17. The method of producing a hollow fiber carbon membrane according to claim 3 , wherein the hydrocarbon gas has from 1 to 4 carbon atoms.

18. The method of producing a hollow fiber carbon membrane according to claim 4 , wherein the carbonization step further comprises supplying an inert gas and the hydrocarbon gas simultaneously, and the concentration of the hydrocarbon gas (volume flow rate of hydrocarbon gas/volume flow rate of inert gas×100[% by volume]) is 5% by volume or more, and 50% by volume or less.

19. The method of producing a hollow fiber carbon membrane according to claim 4 , further comprising elevating a temperature within a reactor while supplying an inert gas in the absence of the hydrocarbon gas before starting the carbonization step.

20. The method of producing a hollow fiber carbon membrane according to claim 4 , wherein the hydrocarbon gas has from 1 to 4 carbon atoms.

Assignees

• Aist

Inventors

• Yoshimune Miki
• Haraya Kenji
• Hara Nobuo

Classifications

• B01D2257/102

  Nitrogen · CPC title

• B01D67/0067 Primary

  by carbonisation or pyrolysis · CPC title

• D01F6/76

  from other polycondensation products · CPC title

• B01D69/08

  Hollow fibre membranes (manufacture of hollow fibres D01D5/24, D01F1/08) · CPC title

• D01D5/24

  with a hollow structure; Spinnerette packs therefor (D01D5/38 takes precedence; producing tubes of plastic material B29D; addition of agents forming hollow filaments D01F1/08) · CPC title