DEVICE FOR PRODUCING CARBON NANOTUBE FIBERS AND METHOD FOR PRODUCING CARBON NANOTUBE FIBERS USING SAME

• US 20170292208A1
• Filed: 10/28/2015
• Published: 10/12/2017
• Est. Priority Date: 10/28/2014
• Status: Active Grant

• Current Assignee: LG Chem Limited (LG Corporation)
• Original Assignee: LG Chem Limited (LG Corporation)
• Inventors: YOON, Ki Yong, LEE, YoungHo, KIM, Ji Eun, CHOE, Yongjin
• Granted Patent: US 10,774,449 B2
• Time in Patent Office: Days
• CPC Class Codes: C01B 2202/08 Aligned nanotubes
• CPC Class Codes: C01B 32/162 characterised by catalysts
• CPC Class Codes: C01B 32/164 involving continuous processes
• CPC Class Codes: C01P 2004/13 Nanotubes
• CPC Class Codes: D01F 11/16 by physicochemical methods
• CPC Class Codes: D01F 9/133 Apparatus therefor

Abstract

The present invention relates to an apparatus for producing a carbon nanotube fiber. The apparatus includes: a vertical reactor having a reaction zone; a concentric double-pipe inlet tube disposed on top of the reaction zone and consisting of an inner pipe through which a spinning feedstock including a spinning solution and a first gas is introduced into the reaction zone and an outer pipe defining a concentric annular portion surrounding the inner pipe and through which a second gas is introduced into the reaction zone; heating means for heating the reaction zone; and a discharge unit disposed under the bottom of the reaction zone to discharge a carbon nanotube fiber therethrough. The spinning feedstock entering the reaction zone through the inner pipe of the inlet tube is carbonized and graphitized while flowing from the top to the bottom of the reaction zone to form a carbon nanotube fiber consisting of a continuous sock (or aggregates) of carbon nanotubes. The second gas entering the reaction zone through the outer pipe of the inlet tube forms a gas curtain surrounding the circumference of the continuous sock of carbon nanotubes while flowing from the top to the bottom of the reaction zone. The gas curtain minimizes the contamination of the inner wall of the reactor and facilitates the discharge of the carbon nanotube fiber. Therefore, the apparatus of the present invention is suitable for the production of a carbon nanotube fiber in a continuous manner.

Claims

1. An apparatus for producing a carbon nanotube fiber, comprising:

a vertical reactor having a reaction zone;

a concentric double-pipe inlet tube disposed on top of the reaction zone and consisting of an inner pipe through which a spinning feedstock comprising a spinning solution and a first gas is introduced into the reaction zone and an outer pipe defining a concentric annular portion surrounding the inner pipe and through which a second gas is introduced into the reaction zone;

heating means for heating the reaction zone; and

a discharge unit disposed under the bottom of the reaction zone to discharge a carbon nanotube fiber therethrough wherein the spinning feedstock entering the reaction zone through the inner pipe of the inlet tube is carbonized and graphitized while flowing from the top to the bottom of the reaction zone to form a carbon nanotube fiber consisting of a continuous sock of carbon nanotubes and wherein the second gas entering the reaction zone through the outer pipe of the inlet tube forms a gas curtain surrounding the circumference of the continuous sock of carbon nanotubes while flowing from the top to the bottom of the reaction zone.

2. The apparatus according to claim 1, wherein the second gas entering from the outer pipe of the inlet tube forms a gas curtain along the inner wall of the reactor so that the continuous sock of carbon nanotubes or the carbon nanotube fiber formed in the reaction zone is physically prevented from approaching the inner wall of the reactor.

3. The apparatus according to claim 1, wherein the second gas entering from the gas inlet tube forms a gas curtain while flowing along the inner wall of the reactor so that a catalyst attached to the inner wall of the reactor is physically removed.

4. The apparatus according to claim 1, wherein an annular opening through which the outer pipe is in communication with the reaction zone is spaced apart from the inner pipe.

5. The apparatus according to claim 4, wherein the annular opening is separated from an opening, through which the inner pipe is in communication with the reaction zone, through an annular thermal insulator positioned between the inner pipe and the outer pipe.

6. The apparatus according to claim 4, wherein the diameters of the gas curtain and the continuous sock of carbon nanotubes are controlled by varying the distance between the inner pipe and the annular opening.

7. The apparatus according to claim 1, wherein the reaction zone consists of a preheating zone and a heating zone and the spinning feedstock introduced into the reaction zone sequentially passes through the preheating zone and the heating zone.

8. The apparatus according to claim 1, further comprising a supply unit for supplying the spinning solution to the inner pipe of the inlet tube, a supply unit for supplying the first gas to the inner pipe of the inlet tube, and a supply unit for supplying the second gas to the outer pipe of the inlet tube.

9. The apparatus according to claim 1, wherein spray means is disposed at an opening through which the inner pipe of the inlet tube is in communication with the reaction zone and the spinning feedstock entering the inner pipe is supplied to the reaction zone through the spray means.

10. The apparatus according to claim 1, wherein the first gas or the second gas is supplied at such a linear velocity that laminar flows are formed in the reaction zone.

11. The apparatus according to claim 8, wherein the first gas supply unit has flow control means by which the first gas is supplied at such a linear velocity that laminar flows are formed and the second gas supply unit has flow control means by which the second gas is supplied at such a linear velocity that laminar flows are formed.

12. The apparatus according to claim 8, wherein the spinning solution supply unit comprises a mixing unit where a catalyst or a catalyst precursor is dispersed in a liquid carbon compound to prepare the spinning solution and a transfer pump for supplying the spinning solution from the mixing unit to the inner pipe of the inlet tube.

13. The apparatus according to claim 1, wherein each of the first gas and the second gas is an inert gas, a reducing gas or a mixed gas thereof.

14. The apparatus according to claim 1, further comprising a circulation line through which each of the first gas and the second gas released from the reactor reenters the reactor for reuse.

15. The apparatus according to claim 1, wherein the spinning solution is a dispersion of a catalyst or a catalyst precursor in a liquid carbon compound.

16. The apparatus according to claim 1, wherein the discharge unit comprises winding means for winding and collecting the carbon nanotube fiber discharged from the bottom of the reactor.

17. The apparatus according to claim 1, wherein the discharge unit has an inlet through which an inert gas is fed to form an inert gas curtain surrounding the circumference of a continuous aggregate of the carbon nanotube fiber discharged from the reaction zone.

18. A method for producing a carbon nanotube fiber using the apparatus according to claim 1.

19. A carbon nanotube fiber produced using the apparatus according to claim 1.