US5227038A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric arc process for making fullerenes
Assignee: Rice University
•
Filing: 1991-10-04
•
Granted: 1993-07-13
•
Expires: 2011-10-04
Abstract
Abstract This invention provides a method of generating fullerenes by vaporizing carbon with the heat from an electrical arc and then condensing a soot from which fullerenes may be recovered.
Inventors
- 👤 Richard E. Smalley
- 👤 Robert E. Haufler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:09
CPC Classifications
B; B82; B82Y; B82Y30/00; B82Y40/00; C; C01; C01B; C01B32/00; C01B32/15; C01B32/152; C01B32/154; Y; Y10; Y10S; Y10S977/00; Y10S977/70; Y10S977/734; Y10S977/742; Y10S977/84; Y10S977/842; Y10S977/843; Y10S977/844; Y10S977/901
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
121 words
A process for making fullerenes comprising: (a) providing a carbon vapor generation zone which comprises a first electrode and a second electrode, (b) maintaining the carbon vapor generation zone in an atmosphere consisting essentially of an atmosphere selected to form fullerene molecules, (c) applying sufficient electrical voltage to the first electrode to maintain an electrical arc between the first electrode and the second electrode, (d) providing a carbon source in close proximity to the electrical arc, so that the carbon source is heated by the electrical arc to form a carbon vapor, (e) passing the carbon vapor to a fullerene condensing zone where the carbon vapor is condensed into a solid carbon soot, and (f) recovering fullerenes from the carbon soot.
Claim 2
Dependent Claim
121 words
A process for making fullerenes comprising: (a) providing a carbon vapor generation zone which comprises a first electrode and a second electrode, (b) maintaining the carbon vapor generation zone in an atmosphere consisting essentially of an atmosphere selected to form fullerene molecules, (c) applying sufficient electrical voltage to the first electrode to maintain an electrical arc between the first electrode and the second electrode, (d) providing a carbon source in close proximity to the electrical arc, so that the carbon source is heated by the electrical arc to form a carbon vapor, (e) passing the carbon vapor to a fullerene condensing zone where the carbon vapor is condensed into a solid carbon soot, and (f) recovering fullerenes from the carbon soot.
Claim 3
Dependent Claim
18 words
A process in accordance with claim 1 wherein either the first electrode or the second electrode comprises carbon.
Claim 4
Dependent Claim
20 words
A process in accordance with claim 1 wherein the first electrode and the second electrode are both comprised of carbon.
Claim 5
Dependent Claim
37 words
A process in accordance with claim 3 wherein the carbon vapor generation zone and the fullerene condensing zone are maintained in an atmosphere consisting essentially of an inert gas at a pressure of 5 to 2000 Torr.
Claim 6
Dependent Claim
26 words
A process in accordance with claim 4 wherein the inert gas is helium and the pressure of the inert gas ranges from 50 to 500 Torr.
Claim 7
Dependent Claim
37 words
A process in accordance with claim 5 wherein the carbon vapor is passed through a fullerene growth and annealing zone maintained at a temperature of 1000 to 2000° C. before being passed to the fullerene condensing zone.
Claim 8
Dependent Claim
28 words
A process in accordance with claim 6 wherein the electrical power supplied to the first electrode ranges from 10 to 500 amps at 10 to 50 volts rms.
Claim 9
Dependent Claim
29 words
A process in accordance with claim 7 wherein the first electrode and the second electrode are maintained apart, to produce an arc gap of between 0.01 and 10 mm.
Claim 10
Dependent Claim
39 words
A process in accordance with claim 4 wherein the inert gas passes through the carbon vapor generation zone, through the fullerene condensing zone, is withdrawn from the fullerene condensing zone and recirculated back to the carbon vapor generation zone.
Claim 11
Dependent Claim
31 words
A process in accordance with claim 1 wherein providing a carbon source in close proximity to the electrical arc is accomplished by passing graphite dust around or through the electrical arc.
Claim 12
Dependent Claim
21 words
A process in accordance with claim 10 wherein the graphite dust is carried to the electrical arc by an inert gas.
Claim 13
Dependent Claim
40 words
A process in accordance with claim 11 wherein the inert gas is helium, and the carbon vapor generation zone and fullerene condensing zone are maintained in an atmosphere consisting essentially of helium at a pressure of 10 to 700 Torr.
Claim 14
Dependent Claim
44 words
A process in accordance with claim 12 further comprising a fullerene growth and annealing zone maintained at a temperature of 1000° to 2000° C., wherein the carbon vapor is passed through the fullerene growth and annealing zone and thereafter to the fullerene condensing zone.
Claim 15
Dependent Claim
46 words
A process in accordance with claim 11 wherein the inert gas passes through the carbon vapor generation zone, through a fullerene growth and annealing zone, through the fullerene condensing zone, is withdrawn from the fullerene condensing zone and recirculated back to the carbon vapor generation zone.
Claim 16
Dependent Claim
29 words
A process in accordance with claim 14 wherein carbon soot is separated from the inert gas before the inert gas is recalculated back to the carbon vapor generation zone.
Claim 17
Dependent Claim
32 words
A process for making fullerenes comprising vaporizing carbon with a plasma in an atmosphere consisting essentially of an atmosphere that promotes fullerene growth and formation thereby forming fullerenes and recovering said fullerenes.
Claim 18
Dependent Claim
32 words
A process for making fullerenes comprising vaporizing carbon with a plasma in an atmosphere consisting essentially of an atmosphere that promotes fullerene growth and formation thereby forming fullerenes and recovering said fullerenes.
Claim 19
Dependent Claim
20 words
A process in accordance with claim 16 where in the plasma is maintained as an electrical arc between two electrodes.
Claim 20
Dependent Claim
29 words
A process in accordance with claim 17 wherein an inert gas circulates and carries vaporized carbon away from the plasma into a zone where fullerene growth and formation occurs.
Claim 21
Dependent Claim
29 words
A process in accordance with claim 18 wherein the inert gas is moved from the zone where fullerene growth and formation occurs and is recirculated back to the plasma.
References Cited (Backward Citations)
US3317354A
Cited
US4767608A
Cited
US4915977A
Cited
SU1587000A1
Cited
JPH02160696A
Cited
JPH02221194A
Cited
WO1992004279A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-07-12 | 1997-01-11 | 1997-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-07-12 | 2001-01-11 | 2001-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-07-12 | 2005-01-11 | 2005-07-13 | $7700.00 | Window Closed / Lapsed |