Method and apparatus for modifying graphene

Patent metadata

Field	Value
Publication number	US-9611149-B2
Application number	US-201414907862-A
Country	US
Kind code	B2
Filing date	Aug 21, 2014
Priority date	Aug 21, 2013
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

There are a method and an apparatus for modifying a graphene, and more specifically, a method and an apparatus for modifying a graphene capable of obtaining the graphene having a desired crystallite size by repeating a process for modifying the graphene using subcritical or supercritical carbon dioxide several times. According to the method and the apparatus for modifying the graphene of the present invention, the graphene having excellent electrical conductivity and dispersibility may be obtained.

First claim

The invention claimed is:

1. A method for modifying a graphene comprising the steps of:
injecting carbon dioxide in a liquid state into a reactor having the graphene;
modifying the graphene by temperature-raising and pressure-raising carbon dioxide to 20 to 50° C. and 73 to 200 atm, respectively;
pressure-releasing and cooling the modified graphene; and
recovering the pressure-released graphene by a recovering bath filled with deionized water.
wherein the steps of temperature-raising and pressure-raising of the carbon dioxide, and pressure-releasing and cooling of the modified graphene are repeated at least two times.

2. The method of claim 1 , wherein the graphene is prepared from at least one kind selected from the group consisting of graphene platelet, graphene nanoplatelet, graphene oxide, graphite, graphite oxide, graphite nanoplatelet, expanded graphite, diamond, fullerene, carbon black, activated carbon, charcoal, carbon nanoribbon, carbon nanowire, carbon nanoclay, carbon nanotube, pitch carbon fiber, carbon nanofiber, carbon glass fiber, and asphalt.

3. The method of claim 1 , wherein the temperature-raising and pressure-raising of the carbon dioxide is performed in the presence of surfactant.

4. The method of claim 1 , wherein the pressure-releasing and cooling of the modified graphene has a temperature of 20 to 30° C.

5. The method of claim 1 , wherein the pressure-releasing and cooling of the modified graphene has a pressure of 1 to 10 atm.

6. The method of claim 1 , further comprising a step of recovering a discharged carbon dioxide from the step of pressure-releasing and cooling the modified graphene.

7. An apparatus for modifying a graphene comprising:
a first modification reactor performing a modification reaction of the graphene;
a carbon dioxide feeding pump feeding carbon dioxide into the first modification reactor;
a raw material injection apparatus injecting the graphene into the first modification reactor;
a first pressure-releaser connected to a rear end of the first modification reactor; and
a recovering bath connected to a rear end of the first pressure-releaser and recovering the graphene in a state in which deionized water is filled into the recovering bath.

Assignees

• Hanwha Chemical Corp

Inventors

• Do Seung Hoe
• Lee Jin Seo
• Jeon Seong Yun
• Kong Jung Ho

Classifications

• C01B2204/32

  Size or surface area · CPC title

• B01J2208/00539

  Pressure · CPC title

• C01B2204/22

  Electronic properties · CPC title

• C01B32/194 Primary

  After-treatment · CPC title

• B01J8/02 Primary

  with stationary particles, e.g. in fixed beds · CPC title