Chemistry: electrical and wave energy – Processes and products – Electrostatic field or electrical discharge
Patent
1995-10-13
2000-08-08
Phasge, Arun S.
Chemistry: electrical and wave energy
Processes and products
Electrostatic field or electrical discharge
42218626, 423448, 4234491, 4234496, 423450, 423445B, C01B 3100
Patent
active
06099696&
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to an apparatus and a method for the conversion of carbon or carbon-containing compounds in a plasma to carbons having a defined nanostructure.
2. Background Art
The production of carbon, for example soots, from carbon or carbon-containing compounds such as, for example, from hydrocarbons in a plasma is known. Thus, for example, GDR Patent Specifications 292 920, 276 098 and 211 457 relate to the production of soot by cracking hydrocarbons, for example methane, in a hydrogen plasma. The cracking is carried out in a so-called plasmatron (for figure see GDR Patent Specification 211 457) in which a hydrogen plasma jet heated to 3500 to 4000 K cracks the injected hydrocarbon. This apparatus can be described as a standard apparatus for the plasma-chemical production of soots from hydrocarbons. The apparatus mentioned and the methods associated therewith are consequently completely suitable for producing the standard carbons such as soot in a reasonable quality. As current knowledge shows, the carbons which can be produced by the known methods, in particular the soots, are not composed, however, of uniform structures but manifest themselves as a wide distribution of different carbon particles having markedly different nanostructure (shown in FIG. 4 as number of particles as a function of the spacing, c/2, between the planes of the layers in pm). The application characteristics of, for example, a soot produced in accordance with the prior art are consequently the result of an average of the characteristics of the different particles. This is unsatisfactory insofar as particular characteristics of carbon particles having defined nanostructure have hitherto not been available.
On the other hand, a controlled production of such carbons with a narrow distribution of carbon particles, i.e. having defined nanostructure, is not achievable with the known apparatuses from the prior art since it is not possible to produce a controllable and homogeneous plasma zone.
BROAD DESCRIPTION OF THE INVENTION
The object was therefore to develop an apparatus which makes it possible to produce very precisely controllable plasma conditions. The object was furthermore to develop a process with the aid of the apparatus which makes it possible to produce carbons having defined nanostructure.
According to the invention, it was possible to achieve the object with the apparatus according to the invention and the corresponding method of the invention.
DESCRIPTION OF THE FIGURES
FIG. 1 shows a first embodiment of the apparatus. Of the three electrodes present, only two are shown.
FIG. 2 shows a second embodiment of the apparatus with a feed device for rapidly cooling the carbon formed.
FIG. 3 shows a portion of the head section of the apparatus. Of the three electrodes present only two are shown.
FIG. 4 shows distribution curves which represent the number of particles as a function of the spacing, c/2, between the planes of the layers for carbons from the prior art (G=graphite, A=acetylene soot, C=soot).
FIG. 5 shows distribution curves corresponding to FIG. 4 which represent the carbons having defined nanostructure produced by the method according to the invention. G=graphite, A'=acetylene soot, C', C"=soots.
FIG. 6 shows the arrangement of three electrodes.
DETAILED DESCRIPTION OF THE INVENTION
The apparatus according to the invention comprises a heat-resistant reaction chamber 1 having a thermally insulating lining, in whose head section 2 that the projected axes form an intersection in the upper section of the reaction chamber 1, fed directly to the electrodes 3, disposed so that a targeted supply is made possible to the plasma zone P formed between the electrodes 3, and
The reaction chamber 1 is expediently of cylindrical design. The insulation 7 of the walls of the reaction chamber is advantageously composed of graphite and, optionally, of an additional ceramic layer. Furthermore, an additional liquid-cooled double wall, which is not shown in greater de
REFERENCES:
patent: 3009783 (1961-11-01), Sheer et al.
patent: 3989512 (1976-11-01), Sayce
patent: 4472254 (1984-09-01), Dotson et al.
patent: 5227038 (1993-07-01), Smalley et al.
patent: 5395496 (1995-03-01), Tsantrizos et al.
Database WPI Week 937, Derwent Publications Ltd., London, GB, AN 93-055086 & JP, A, 5 004 810 (Semiconductor Energy Lab.), Jan. 1994.
International Publication No. WO 86/02024, published Apr. 1986.
Fischer Francis
Fulcheri Laurent
Schwob Yvan
Willemez Pierre
Armines
Mayekar Kishor
Phasge Arun S,.
Timcal Ltd.
LandOfFree
Conversion of carbon or carbon-containing compounds in a plasma does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Conversion of carbon or carbon-containing compounds in a plasma, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Conversion of carbon or carbon-containing compounds in a plasma will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1146831