Catalyst for mass production of multi-wall carbon nanotubes

Patent metadata

Field	Value
Publication number	US-11524277-B2
Application number	US-201816490765-A
Country	US
Kind code	B2
Filing date	Mar 2, 2018
Priority date	Mar 3, 2017
Publication date	Dec 13, 2022
Grant date	Dec 13, 2022

Abstract

Provided is a catalyst for manufacturing multi-wall carbon nanotubes, the catalyst including metal components according to <Equation> Ma:Mb=x:y, and having a hollow structure with a thickness of 0.5-10 μm. In the above equation, Ma represents at least two metals selected from Fe, Ni, Co, Mn, Cr, Mo, V, W, Sn, and Cu; Mb represents at least one metal selected from Mg, Al, Si, and Zr; x and y each represent the molar ratio of Ma and Mb; and x+y=10, 2.0≤x≤7.5, and 2.5≤y≤8.0.

First claim

The invention claimed is:

1. A catalyst for preparing multi-walled carbon nanotubes, the catalyst having a hollow structure with a thickness of 0.5 μm to 10 μm and consisting of Ma and Mb according to the following Equation:
Ma:Mb=x:y,   <Equation>

wherein:
Ma represents two or more metals selected from among Fe, Ni, Co, Mn, Cr, Mo, V, W, Sn, and Cu;
Mb is one or more metals selected from among Al, Si, and Zr;
x and y represent mole fractions of Ma and Mb, respectively; and
x+y=10, 4.10≤x≤7.27, and 2.73≤y≤5.90, and
wherein the catalyst has an apparent density of 0.084 g/mL to 0.662 g/mL.

2. The catalyst of claim 1 , wherein the thickness of the catalyst is 1 μm to 8 μm.

3. The catalyst of claim 1 , wherein the hollow structure has a hollow ratio of 50 vol % or more.

4. A carbon nanotube aggregate, which comprises a bundle carbon nanotube consisting of a plurality of multi-walled carbon nanotubes grown on the catalyst of claim 1 .

5. The carbon nanotube aggregate of claim 4 , wherein the bundle carbon nanotube has an average bundle diameter of 0.5 μm to 20 μm and an average bundle length of 10 μm to 200 μm.

6. The carbon nanotube aggregate of claim 4 , wherein the multi-walled carbon nanotubes have an intensity ratio (IG/ID) of 0.7 to 1.5 as measured by Raman spectroscopy.

7. The carbon nanotube aggregate of claim 4 , wherein the multi-walled carbon nanotubes have an average diameter of 5 nm to 50 nm.

8. The carbon nanotube aggregate of claim 4 , wherein the multi-walled carbon nanotubes have an apparent density of 0.01 g/mL to 0.07 g/mL.

9. A catalyst for preparing multi-walled carbon nanotubes, the catalyst having a hollow structure with a thickness of 0.5 μm to 10 μm for synthesis of carbon nanotube in a high yield of 2,600-4,282%, wherein the yield is the weight of synthesized carbon nanotube divided by the weight of introduced catalyst and multiplied by 100, and comprising metal components according to the following Equation:
Ma:Mb=x:y,   <Equation>

wherein:
Ma represents two or more metals selected from among Fe, Ni, Co, Mn, Cr, Mo, V, W, Sn, and Cu;
Mb is one or more metals selected from among Al, Si, and Zr;
x and y represent mole fractions of Ma and Mb, respectively; and
x+y=10, 4.10≤x≤7.27, and 2.73≤y≤5.90, and
wherein the catalyst has an apparent density of 0.084 g/mL to 0.662 g/mL, and
wherein the catalyst is selected from among the following metal component compositions:
Fe, Co, Mo, and Al;
Fe, Co, Mo, V, and Al;
Co, V, W, and Al; and
Co, V, Al, and Zr.

Assignees

• Korea Kumho Petrochemical Co Ltd

Inventors

• Ryu Sang Hyo
• Sung Hyun Kyung
• Jeong Chung Heon
• Kim Dong Hwan

Classifications

• C01P2002/74

  by peak-intensities or a ratio thereof only · CPC title

• C01P2006/10

  Solid density · CPC title

• B01J23/882

  and cobalt · CPC title

• C01B2202/36

  Diameter · CPC title

• B01J23/002

  Mixed oxides other than spinels, e.g. perovskite · CPC title