Method and apparatus for preparing a collection surface for use in producing carbon nanostructures

• US 20060008406A1
• Filed: 12/29/2004
• Published: 01/12/2006
• Est. Priority Date: 07/09/2004
• Status: Active Grant

• Current Assignee: Clean Technology International Corp.
• Original Assignee: Clean Technology International Corp.
• Inventors: Wagner, Anthony S.
• Granted Patent: US 7,563,426 B2
• Time in Patent Office: Days
• US Class Current: 423/445.R
• CPC Class Codes: B01J 19/24 Stationary reactors without moving elements inside B01J19/08, B01J19/26 take precedence; with stationary particles B01J8/02
• CPC Class Codes: B01J 19/26 Nozzle-type reactors, i.e. the distribution of the initial reactants within the reactor is effected by their introduction or injection through nozzles
• CPC Class Codes: B01J 21/185 Carbon nanotubes carbon nanotubes per se C01B32/15
• CPC Class Codes: B01J 2219/00119 Heat exchange inside a feeding nozzle or nozzle reactor
• CPC Class Codes: B01J 2219/00135 Electric resistance heaters
• CPC Class Codes: B01J 2219/00182 controlling the level of reactants in the reactor vessel
• CPC Class Codes: B01J 23/10 of rare earths
• CPC Class Codes: B01J 23/24 Chromium, molybdenum or tungsten
• CPC Class Codes: B01J 23/38 of noble metals
• CPC Class Codes: B01J 23/70 of the iron group metals or copper
• CPC Class Codes: B01J 37/023 using molten compounds
• CPC Class Codes: B01J 4/002 Nozzle-type elements nozzle-type reactors B01J19/26
• CPC Class Codes: B01J 6/005 Fusing
• 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: C01B 32/162 characterised by catalysts
• CPC Class Codes: C01B 32/90 Carbides
• CPC Class Codes: Y10S 977/842 for carbon nanotubes or fullerenes
• CPC Class Codes: Y10S 977/844 Growth by vaporization or dissociation of carbon source using a high-energy heat source, e.g. electric arc, laser, plasma, e-beam

Abstract

A method includes producing deposition conditions in a collection area above a reactant liquid containing one or more catalyst metals. The reactant liquid is maintained under conditions in which atoms of the catalyst metal may escape from the reactant liquid into the collection area. A suitable carrier gas is directed to traverse a surface of the reactant liquid and flow along a collection path that passes over a collection surface in the collection area. This flow of carrier gas is maintained so that escaped atoms of catalyst metal are entrained in the gas traversing the surface of the reactant liquid and are deposited on the prior to or concurrently with nanocarbon structure formation at the collection surface.

Claims

1. A method including:

(a) producing deposition conditions in a collection area above a reactant liquid containing one or more catalyst metals;

(b) maintaining the reactant liquid under conditions in which atoms of the catalyst metal escape from the reactant liquid into the collection area; and

(c) directing a carrier gas to traverse a surface of the reactant liquid and flow along a collection path that passes over a collection surface in the collection area, the flow of carrier gas being maintained so that escaped atoms of catalyst metal are entrained in the carrier gas traversing the surface of the reactant liquid and are deposited on the collection surface.

2. The method of claim 1 wherein the collection surface is maintained at a temperature between approximately 600 degrees Celsius to approximately 1950 degrees Celsius.

3. The method of claim 1 wherein the reactant liquid includes liquid aluminum at a temperature at or above 650 degrees Celsius, together with one or more catalyst metals selected from a group consisting of iron, cobalt, molybdenum, lithium, copper, and titanium.

4. The method of claim 1 wherein the step of producing the deposition conditions includes purging the collection area of oxygen.

5. The method of claim 1 wherein the catalyst metal comprises a metal with one, two, three, four, or five electrons in the outer valence shell.

6. The method of claim 1 wherein the carrier gas includes one or more purge gases selected from a group consisting of nitrogen, helium, argon, carbon monoxide, and heater burner flue gasses.

7. The method of claim 1 further including:

(a) injecting a feed material into the reactant liquid, the feed material comprising a quantity of a first type of hydrocarbon compound;

(b) maintaining the hydrocarbon molecules of the first type of hydrocarbon compound and any reaction products in contact with the reactant liquid for a period of time sufficient to liberate carbon atoms from the hydrocarbon molecules of the first type of hydrocarbon compound or reaction products and place the liberated carbon atoms in an excited state; and

(c) enabling the liberated carbon atoms in the excited state to traverse the surface of the reactant liquid and flow along the collection path through the collection area so that the liberated carbon atoms pass over the collection surface in the collection area under conditions in which the liberated carbon atoms are enabled to phase change to the ground state on the collection surface.

8. A method including:

(a) liberating atoms of a catalyst metal from a reactant liquid; and

(b) entraining the liberated atoms of catalyst metal in a flow of carrier gas and directing the flow of carrier gas and entrained atoms of catalyst metal across a collection surface under deposition conditions at which the liberated atoms of catalyst metal are deposited on the collection surface.

9. The method of claim 8 further including the step manipulating the flow of carrier gas to produce a low pressure area adjacent to the collection surface.

10. The method of claim 8 further including the step of maintaining the collection surface at temperature of between approximately 600 degrees Celsius to approximately 1950 degrees Celsius.

11. The method of claim 8 wherein the reactant liquid includes predominantly aluminum at a temperature above approximately 900 degrees Celsius, together with one or more catalyst metals.

12. The method of claim 8 wherein the step of directing the carrier gas and entrained atoms of catalyst metal across the collection surface includes deflecting the carrier gas and entrained atoms of catalyst metal along a flow path transverse to a line extending perpendicular to an upper surface of the reactant liquid.

13. The method of claim 8 wherein the catalyst metal comprises a metal with one, two, three, four, or five electrons in the outer valence shell.

14. The method of claim 8 wherein the carrier gas includes one or more gases selected from a group consisting of nitrogen, helium, argon, carbon monoxide, water vapor, and heater burner flue gasses.

15. The method of claim 8 further including:

(a) liberating carbon atoms from hydrocarbon molecules by reduction reaction with the reactant liquid and maintaining the liberated carbon atoms in an excited state; and

(b) enabling the liberated carbon atoms in the excited state to traverse an upper surface of the reactant liquid; and

(c) directing the liberated carbon atoms in the excited state across the collection surface under collection conditions at which the liberated carbon atoms in the excited state phase change to a ground state by carbon nanostructure self-assembly.

16. An apparatus including:

(a) a reactant liquid vessel for containing a reactant liquid at a reactant liquid level, the reactant liquid including a quantity of at least one catalyst metal;

(b) an injection arrangement for injecting a stream of feed material into the reactant liquid vessel at a point below the reactant liquid level;

(c) a collection chamber positioned to receive effluent escaping from the reactant liquid in the reactant liquid vessel in an effluent ejection area;

(d) a collection surface forming a surface in the collection chamber, the collection surface residing at a position above the reactant liquid level and adjacent to the effluent ejection area; and

(e) a collection surface charging device operatively connected to the collection surface to produce a desired electrical charge on the collection surface.

17. The apparatus of claim 16 wherein the collection surface includes a portion extending in a plane transverse to a device vertical axis.

18. The apparatus of claim 16 further including a deflecting surface forming a portion of the collection chamber, the deflection surface extending transverse to the device vertical axis in position to deflect materials escaping from the reactant liquid vessel in the effluent ejection area so as to flow across the collection surface.

19. The apparatus of claim 16 further including a reaction chamber portion of the reactant liquid vessel, the reaction chamber portion including an upper wall located below the reactant liquid level in the reactant liquid vessel.

20. The apparatus of claim 16 wherein the collection surface includes graphite.

21. The apparatus of claim 16 further including a water injector conduit extending into the collection chamber.

22. The apparatus of claim 16 further including at least one heating element positioned to apply heat to one or more surfaces defined in the collection chamber.

23. A method for producing carbon nanostructures, the method including:

(a) producing a collection atmosphere in a collection area above a reactant liquid;

(b) injecting a feed material into the reactant liquid, the feed material including a quantity of a carbon-bearing compound;

(c) maintaining the molecules of the carbon-bearing compound and any reaction products in contact with the reactant liquid for a period of time sufficient to liberate carbon atoms from the molecules of the carbon-bearing compound or reaction products and place the liberated carbon atoms in an excited state;

(d) enabling the liberated carbon atoms in the excited state to traverse a surface of the reactant liquid and flow along a collection path through the collection area so that the liberated carbon atoms pass over a collection surface in the collection area under conditions in which the liberated carbon atoms are enabled to phase change to the ground state on the collection surface; and

(e) enabling hydrogen atoms that traverse the surface of the reactant liquid to flow in a direction away from the collection surface while the liberated carbon atoms pass over the collection surface.

24. The method of claim 23 further including applying heat to the collection area from at least one boundary wall defining the collection area.

25. The method of claim 23 wherein enabling hydrogen atoms to flow in the direction away from the collection surface includes venting material from the collection area while the liberated carbon atoms pass over the collection surface.

26. The method of claim 23 wherein enabling hydrogen atoms to flow in the direction away from the collection surface includes maintaining an open system in the collection area while the liberated carbon atoms pass over the collection surface.

27. The method of claim 23 further including adding water vapor to the collection area while the liberated carbon atoms pass over the collection surface.

28. A method for producing carbon nanostructures, the method including:

(a) liberating carbon atoms from carbon-bearing molecules by reduction reaction with a reactant liquid and maintaining the liberated carbon atoms in an excited state;

(b) enabling the liberated carbon atoms in the excited state to traverse a surface of the reactant liquid;

(c) directing the liberated carbon atoms in the excited state across a collection surface under collection conditions at which the liberated carbon atoms in the excited state phase change to a ground state by carbon nanostructure self-assembly; and

(d) enabling hydrogen atoms that traverse the surface of the reactant liquid to flow in a direction away from the collection surface while the liberated carbon atoms are directed across the collection surface.

29. The method of claim 28 further including applying heat to a collection area adjacent to the collection surface, the heat being applied from at least one boundary wall defining the collection area.

30. The method of claim 29 wherein enabling hydrogen atoms to flow in the direction away from the collection surface includes venting material from the collection area while the liberated carbon atoms are directed across the collection surface.

31. The method of claim 29 wherein enabling hydrogen atoms to flow in the direction away from the collection surface includes maintaining an open system in the collection area while the liberated carbon atoms are directed across the collection surface.

32. The method of claim 29 further including adding water vapor to the collection area while the liberated carbon atoms are directed across the collection surface.

33. A method including:

(a) directing a stream of extraneous atoms and liberated carbon atoms in an excited state into a collection area;

(b) separating at least some of the extraneous atoms from the stream of extraneous atoms and liberated carbon atoms in the excited state to produce an excited carbon atom rich stream;

(c) directing the excited carbon atom rich stream across a collection surface; and

(d) directing the extraneous atoms separated from the stream of extraneous atoms and liberated carbon atoms in the excited state in a direction away from the collection surface.

34. The method of claim 33 wherein directing extraneous atoms in the direction away from the collection surface includes venting material from a collection area in which the collection surface is located, the venting occurring while the carbon atom rich stream is directed across the collection surface.

35. The method of claim 33 wherein directing extraneous atoms in the direction away from the collection surface includes maintaining an open system in a collection area in which the collection surface is located, the open system being maintained while the excited carbon atom rich stream is directed across over the collection surface.