Process for preparing catalyst composition for the synthesis of carbon nanotube with high yields using the spray pyrolysis method

• US 9,006,132 B2
• Filed: 05/11/2011
• Issued: 04/14/2015
• Est. Priority Date: 08/10/2010
• Status: Active Grant

• Current Assignee: Korea Kumho Petrochemical Co Limited (Korea Kumho Petrochemical)
• Original Assignee: Korea Kumho Petrochemical Co Limited (Korea Kumho Petrochemical)
• Inventors: Ryu, Sang-Hyo, Sung, Hyun-Kyung, Choi, Namsun, Lee, Wan Sung, Kim, Dong Hwan, Jang, Youngchan
• Primary Examiner(s): Dunn, Colleen
• Assistant Examiner(s): Soliman, Haytham
• Application Number:
  US13/105,663
• Publication Number:
  US 20120040186A1
• Time in Patent Office: 1,434 Days
• Field of Search: 502/306, 502/328, 502/324, 502/325, 502/338, 502/340, 423/447.4, 423/447.2, 423/447.1, 423/447.3, 423/455, 977/896, 977/752, 977/742, 977/740, 977/840, 977/842
• US Class Current: 502/328
• CPC Class Codes: B01J 23/745 Iron
• CPC Class Codes: B01J 23/75 Cobalt
• CPC Class Codes: B01J 23/78 with alkali- or alkaline earth metals
• CPC Class Codes: B01J 23/8872 Alkali or alkaline earth metals
• CPC Class Codes: B01J 35/30 characterised by their physical properties
• CPC Class Codes: B01J 37/082 Decomposition and pyrolysis
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: B82Y 40/00 Manufacture or treatment of nanostructures
• CPC Class Codes: D01F 9/12 Carbon filaments; Apparatus specially adapted for the manufacture thereof
• CPC Class Codes: D01F 9/127 by thermal decomposition of hydrocarbon gases or vapours or other carbon-containing compounds in the form of gas or vapour, e.g. carbon monoxide, alcohols
• CPC Class Codes: D01F 9/1273 Alkenes, alkynes
• CPC Class Codes: Y10S 977/74 Modified with atoms or molecules bonded to the surface
• CPC Class Codes: Y10S 977/742 Carbon nanotubes, CNTs
• CPC Class Codes: Y10S 977/84 Manufacture, treatment, or detection of nanostructure
• CPC Class Codes: Y10S 977/842 for carbon nanotubes or fullerenes
• CPC Class Codes: Y10T 428/298 Physical dimension

Abstract

The present invention relates to a process for preparing catalyst composition for the synthesis of carbon nanotube with high yields using the spray pyrolysis method. More particularly, this invention relates to a process for preparing catalyst composition for the synthesis of carbon nanotube comprising the steps of i) dissolving multi-component metal precursors of catalyst composition in de-ionized water; ii) spraying obtained catalytic metal precursor solution into the high temperature reactor by gas atomization method; iii) forming the catalyst composition powder by pyrolysis of gas atomized material; and iv) obtaining the catalyst composition powder, wherein said catalyst composition comprises i) main catalyst selected from Fe or Co, ii) Al, iii) optional co-catalyst at least one selected from Ni, Cu, Sn, Mo, Cr, Mn, V, W, Ti, Si, Zr or Y, iv) inactive support of Mg. Further, the catalyst composition prepared by this invention has a very low apparent density of 0.01˜0.50 g/ml as well as the catalyst composition affords high production yield (1,000˜1,800%) of carbon nanotube.

Claims

1. A process for preparing catalyst composition having the apparent density of 0.01-0.50 g/ml for the synthesis of carbon nanotube in a high yield of 1,000-1,800% comprising the steps of:

i) dissolving multi-component metal precursors of catalyst composition in deionized water;

ii) spraying obtained catalytic metal precursor solution into the high temperature reactor by gas atomization method using 2-5 atm pressure of air;

iii) forming the catalyst composition powder by pyrolysis of gas atomized material at the temperature in the range of 600-1,200°

C.; and

iv) obtaining the catalyst composition powder,

wherein said catalyst composition is represented by following formula

[Fe_a;

Al_b]_x;

M_y;

Mg_z;

wherein

Fe represents catalytic metal of iron or its oxide;

Al represents catalytic metal of aluminum or its oxide;

Mg represents inactive support of magnesium or its oxide;

M represents at least one transition metal selected from Co, Ni, Cr, Mn, Mo, W, V, Sn, or Cu or its oxide;

x, y, and z represent molar fraction of [the sum of Fe and Al], M, and Mg,

wherein

 

x+y+z=10, 2.0≦

x≦

8.0, 0.0≦

y≦

2.5, 0.5≦

z≦

8.0;

 

a and b represent molar fraction of Fe and Al;

 

a+b=10, 2.0≦

a≦

5.5, 4.5≦

b≦

8.0; and

wherein said metal precursor is at least one selected from nitrate, sulfate, alkoxide and/or carbonate form of metal.

2. The process for preparing catalyst composition according to claim 1, wherein said pyrolysis is performed at the temperature in the range of 600-1,000°

C.

3. The process for preparing catalyst composition according to claim 1, wherein said pyrolysis is performed at the pressure of spray gas in the range of 2-4 atm and the spray gas is air.

4. The process for preparing catalyst composition according to claim 1, wherein apparent density of catalyst composition is in the range of 0.03-0.40 g/ml.