CN1093507C - Preparation of carbon nanometer pipe material and its equipment - Google Patents
Preparation of carbon nanometer pipe material and its equipment Download PDFInfo
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- CN1093507C CN1093507C CN01122772A CN01122772A CN1093507C CN 1093507 C CN1093507 C CN 1093507C CN 01122772 A CN01122772 A CN 01122772A CN 01122772 A CN01122772 A CN 01122772A CN 1093507 C CN1093507 C CN 1093507C
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Abstract
The present invention discloses the technical scheme of a method and a device for preparing carbon nanotube material, which belongs to the crossed field of coal science, an applied science thereof and material science. The present invention is characterized in that the preparation of nanometer-level catalyst granules, the mixing of a catalyst and raw material, and the synthesis of the carbon nanotube material are completed once, that is, the carbon nanotube material is prepared by a means that carbonaceous material and the catalyst granules are directly sprayed into plasma jet. The method has the characteristics of low raw material cost, easy operation, short technological process, stable system operation, etc. The device has the advantages of novel structure and advanced means, and the carbon nanotube material prepared by the device and the method has wide application area.
Description
One, technical field
The preparation of carbon nano-tube material and device belong to the crossing domain of coal science and applied science and Materials science, be specifically a kind of be a kind of method and apparatus that raw material using plasma jet means prepare carbon nano-tube material with the carbonaceous material.
Two, background technology
Carbon nanotube is a kind of type material of having found since 1991 (Ijima S., [Nature 354,56,1991]), is one of focus of paying close attention to of people to its preparation always.People such as Ebbesen (Ebbesen T.W., Ajayan P.M., [Nature, 356,1992]) adopt two graphite rods to be respectively anode and negative electrode, carry out direct-current discharge in 500Torr atmosphere under 10～18V, 100A current condition.Anode constantly is consumed, and sediment pile is then constantly arranged on the negative electrode, and carbon nanotube is enclosed in formed settling inside.This method mainly is to rely on pyritous electric arc direct evaporation graphite rod, and the graphite raw material of use is also more expensive, and owing to there is the continuous consumption of electrode, so electric arc work is stable poor, the limitation of length of Graphite Electrodes this method move for a long time.Although Pang is (Pang L.S.K., Wilson M.A., [Energy ﹠amp; Fuels, 7,436,1993]) also used coal to do raw material, but he still adopts coal-based rod as electrode, so its preparation method is similar with graphite/arc process.The method for preparing carbon nanotube in addition mainly also has catalystic pyrolysis (being called the CVD method again), is raw material but this method adopts acetylene, and is also relatively more expensive.
Three, summary of the invention
The purpose of carbon nano-tube material preparation of the present invention and device has been to overcome the shortcoming of raw material costliness in the above-mentioned prior art and has used raw material as the caused various defectives of electrode, thereby disclosing cheap coal, carbon materials, rubber powder and other carbonaceous material of a kind of direct employing is raw material, the technical scheme of synthesize nano carbon tube material and device under the situation that does not influence arc stability work.
The preparation method of a kind of carbon nano-tube material of the present invention, it is characterized in that it being a kind of with carbonaceous material and metal, metal oxide, nonmetal, nonmetal oxide catalyst mix, prepare the method for carbon nanotube by means among the plasma jet that carbonaceous material and granules of catalyst are directly sprayed into, just a synthetic step of the mixing of the preparation of nm-class catalyst particulate, catalyzer and raw material and carbon nanotube finishes.Its concrete steps and processing condition are: the mixing of I, the working gas hydrogen that feeds plasma generator, argon gas, nitrogen or theirs
Close gas, connect power supply and light plasma generator, plasma generator
Electrode is a metallic substance, and II, feeding carrier gas argon gas, hydrogen, nitrogen, methane gas, oil liquefied gas will be crushed to
0～10% granules of catalyst of the carbonaceous material that 200 orders are following and its weight percent
Mix injecting directly in the arc plasma jet, under effect, promptly make at jet
Carbon nano-tube material, the processing condition that adopted in III, the preparation process: the producer worker of DC arc plasma
The rate of doing work is 30～45KW; The plasma generator working gas is hydrogen and argon gas
Mixed gas, their flow is respectively 4.2～6.2m
3/ h and 1.2～3.2m
3/ h; Adopt
With argon gas is carrier gas, and flow is 0.7～2.7m
3/ h; For powder speed is 0.5～4.0g/s;
The carbonaceous material granularity is below 200 orders, and the working pressure of system is a normal pressure, during stop
Between 4～8ms.
The preparation of above-mentioned preparation carbon nano-tube material is characterized in that the carbonaceous material that uses is raw coal, carbon materials, rubber tyre and other carbonaceous material.
The preparation of above-mentioned preparation carbon nano-tube material is characterized in that described catalystic material comprises micron order and nano level Al, Ca, and Cu, Mn, Ni, Pt, Fe, Co, La, W, Au, metals such as Pd also comprise micron order and nanosize metal oxide LaO, Al
2O
3, Mo
2O
5, TiO
2, Fe
2O
3, CuO and non-metal particle Si, SiO
2
The preparation of above-mentioned preparation carbon nano-tube material is characterized in that the employed metal electrode material of plasma generator is Al, Ca, Cu, Mn, Ni, Pt, Fe, Co, La, W, Au, the Pd metallic substance, and with these materials preparation-obtained and alloy electrode.
The preparation of above-mentioned preparation carbon nano-tube material is characterized in that the hybrid mode of carbonaceous material and catalyzer is: I. directly mixed carbonaceous material and micron order catalyzer before spraying, and mixture is done
For raw material directly sprays among the plasma jet, or II. micron order catalyzer and carbonaceous material be by different position stream penetratings, the catalyzer spray
The implantation site sprays into 20～50mm on the position at coal dust, or III. directly sprays into carbonaceous material, and simultaneously directly and the generation of electric arc splash-proofing sputtering metal electrode receive
The meter level catalyzer mixes in jet.
The device of realizing above-mentioned carbon nano-tube material preparation is characterized in that: primary device comprises plasma generator 1, feeder 2, reactor 3, collector more than 4 parts are formed, auxiliary unit has for powder part 8, the recirculated cooling water part, supplying unit 10 and air path part: hydrogen source gas 5, argon gas origin 6, for powder gas circuit 7 and balance gas circuit 9, from top to bottom, the order of connection of primary device is arc plasma generator (1) feeder (2) reactor (3) collector (4), the exit diameter of arc plasma generator 1 is 10～20mm, feeder 2 tightly is positioned under the arc plasma generator 1, feeder 2 centre portionss are diameter plasma jet passages at 10～30mm, the jet that comes out from arc plasma generator 1 is from passing through here, it is the feed nozzle of 3～5mm that feeder 2 has two diameters, the vertical range of first nozzle distance arc plasma generator 1 jet exit is 15mm, the vertical range of first nozzle distance arc plasma generator 1 jet exit is 35～65mm, pass through nozzle, catalyzer and carbon compound can be directly by among the stream penetratings, and then under the feeder reactor 3, reactor 3 is a tubular structure, diameter is 10～30mm, and length is 300～350mm.
The advantage of the inventive method:
The electric arc jet that adopts among the present invention is produced by plasma generator, and it is a system that works alone, and the electrode of producer does not participate in the reaction that carbon nanotube generates; Raw material is admitted to jet area, rather than the work area of electric arc, so electric arc work is not subjected to it to disturb working stability.The electrode of producer is not consumed owing to synthesizing carbon nanotubes, so its cycle of operation is long, and raw material then can constantly infeed, so this method possesses the condition that serialization is produced.The raw material that adopts is a coal, and it is compared on cost with graphite and acetylene and takes advantage.
Four, description of drawings
Fig. 1 is a kind of device synoptic diagram for preparing the method for carbon nanotube of the present invention.
Number in the figure is: (1) dc arc plasma generator, and (2) feeder, (3) reactor, (4) collector, (5) hydrogen source gas, (6) argon gas source of the gas (7) is for powder gas circuit, (8) powder feeder, (9) balance gas circuit, (10) power supply.
Fig. 2 is the photo that utilizes institute of the present invention synthetic carbon nanotube that scanning electronic microscope is taken.
Fig. 3 is the high resolution photo that utilizes institute of the present invention synthetic carbon nanotube that transmission electron microscope is taken.
Five, embodiment
Below in conjunction with figure and example the present invention will be described in detail:
Apparatus of the present invention mainly are made up of arc plasma generator 1, feeder 2, reactor 3, collector 4 and air feed part and supplying unit 10.Gas circuit comprises hydrogen source gas 5, argon gas source of the gas 6, is Fig. 1 for powder gas circuit 7, powder feeder 8 and balance gas circuit 9. whole schematic representation of apparatus. reactor is a tubular reactor, and reactor wall is a graphite bushing, and the outer wall of reactor is a water-cooling jacket.After opening hydrogen source gas 5 and argon gas source of the gas 6 valves, connect power supply 10, light direct current arc, the mixed gas of hydrogen and argon gas forms plasma jet later on by electric arc, and through feeder 2 and reactor 3. unlatching powder feeders 8, the raw material of powder feeder 8 outputs is sprayed in the plasma jet by feeder 2 under for the drive of powder carrier gas 7, and the effect of balance carrier gas 9 is the pressure between the material bed up and down within the balance powder feeder 8.Be reflected in the reactor 3 and carry out, mix with coking material on the graphite inwall of a part of carbon nanotube of generation in reactor 3, another part carbon nanotube of generation and the reaction residues in the collector 4 mix.
Embodiment 1
The employing shenfu coal is a raw material, pulverizes the back coal powder size about 200 orders.Adopt H
2/ Ar arc plasma jet, the power of producer are 40kW; Hydrogen flowing quantity is 5.0m
3/ h, argon flow amount are 1.8m
3/ h, carrier gas flux are 1.2m
3/ h; For powder speed is 2.5g/s; React after 5 minutes, by observing a large amount of carbon nanotube (see figure 2)s in the settling of scanning electron microscope on reactor graphite inwall.
Adopting the Baode coal is raw material, pulverizes the back coal powder size about 200 orders, and the iron powder that adds raw coal weight 5% is made catalyzer.Adopt H
2/ Ar arc plasma jet, the power of producer are 42kW; Hydrogen flowing quantity is 5.2m
3/ h, argon flow amount are 2.2m
3/ h, carrier gas is an argon gas, flow is 1.7m
3/ h; For powder speed is 1.5g/s; React after 8 minutes, can be in the settling on reactor graphite inwall by transmission electron microscope observing to a large amount of carbon nanotubes.The external diameter of carbon nanotube is 100 nanometers, and internal diameter is 30 nanometer (see figure 3)s.
Adopting the Baode coal is raw material, pulverizes the back coal powder size about 200 orders, and the cobalt powder that adds raw coal weight 7% is made catalyzer.Adopt H
2/ Ar arc plasma jet, the power of producer are 40kW; Hydrogen flowing quantity is 5.2m
3/ h, argon flow amount are 2.2m
3/ h, carrier gas is an argon gas, flow is 1.7m
3/ h; For powder speed is 3.0g/s; React after 10 minutes, by in the settling of transmission electron microscope on reactor graphite inwall and the carbon nano-tube material that can observe a kind of special construction in the pyrolysis residue in the collector, between the tube wall graphite synusia of this carbon nanotube parallel to each other but with the axially incline of pipe, graphite synusia and axial angle are 25 °～30 °.
Embodiment 4
Adopting the Baode coal is raw material, pulverizes the back coal powder size about 200 orders, adds the Al of raw coal weight 3%
2O
3Powder is made catalyzer.Adopt H
2/ Ar arc plasma jet, the power of producer are 45kW; Hydrogen flowing quantity is 5.2m
3/ h, argon flow amount are 2.2m
3/ h, carrier gas is an argon gas, flow is 1.7m
3/ h; For powder speed is 1.6g/s; React after 6 minutes, by observing a large amount of carbon nanotubes in the settling of transmission electron microscope on reactor graphite inwall and in the pyrolysis residue in the collector.
Adopting the Baode coal is raw material, pulverize the back coal powder size about 200 orders, raw coal is sprayed into plasma jet from different positions respectively with the iron powder catalyzer, and the position that catalyzer sprays into is positioned at arc plasma generator outlet 20mm place down, is positioned at coal dust and sprays into 30mm on the place.Adopt H
2/ Ar arc plasma jet, the power of producer are 42kW; Hydrogen flowing quantity is 5.2m
3/ h, argon flow amount are 2.2m
3/ h, the coal dust carrier gas is an argon gas, flow is 1.7m
3/ h; The catalyzer carrier gas is an argon gas, and flow is 2.1m
3/ h; For powder speed is 2.2g/s; The feed rate of catalyzer is 0.18g/s; React after 5 minutes, by observing a large amount of carbon nanotubes in the settling of transmission electron microscope on reactor graphite inwall and in the pyrolysis residue in the collector.
Adopting the Baode coal is raw material, pulverize the back coal powder size about 200 orders, raw coal is sprayed into plasma jet from different positions respectively with CuO powder catalyzer, and the position that catalyzer sprays into is positioned at arc plasma generator outlet 20mm place down, is positioned at coal dust and sprays into 30mm on the place.Adopt H
2/ Ar arc plasma jet, the power of producer are 42kW; Hydrogen flowing quantity is 5.2m
3/ h, argon flow amount are 2.2m
3/ h, the coal dust carrier gas is an argon gas, flow is 1.7m
3/ h; The catalyzer carrier gas is an argon gas, and flow is 2.1m
3/ h; Coal supply powder speed is 3.6g/s; The feed rate of catalyzer is 0.22g/s; React after 5 minutes, by observing a large amount of carbon nanotubes in the settling of transmission electron microscope on reactor graphite inwall and in the pyrolysis residue in the collector.
Claims (10)
1, a kind of preparation method of carbon nano-tube material is characterized in that: the carbonaceous material below 200 orders is sprayed in the plasma jet.
2, according to the preparation method of the described carbon nano-tube material of claim 1, it is characterized in that the carbonaceous material below 200 orders and metal, metal oxide, nonmetal, nonmetal oxide catalyst mix, among carbonaceous material and granules of catalyst are directly sprayed into plasma jet, prepare carbon nanotube.
3, according to the preparation method of the described carbon nano-tube material of claim 1, the working gas that it is characterized in that feeding plasma generator is hydrogen, argon gas, nitrogen or their mixed gas, connect power supply and light plasma generator, the electrode of plasma generator is a metallic substance.
4, according to the preparation method of the described carbon nano-tube material of claim 1; it is characterized in that feeding carrier gas argon gas, hydrogen, nitrogen, methane gas or oil liquefied gas; 0～10% the granules of catalyst that is crushed to carbonaceous material below 200 orders and its weight percent mixed injecting directly in the arc plasma jet, under jet action, make carbon nano-tube material.
5, according to the preparation method of the described carbon nano-tube material of claim 1, the processing condition that it is characterized in that in the preparation process being adopted: the producer operating power of DC arc plasma is 30～45KW; The plasma generator working gas is the mixed gas of hydrogen and argon gas, and their flow is respectively 4.2～6.2m
3/ h and 1.2～3.2m
3/ h; It is carrier gas that argon gas is adopted in coal powder injection, and flow is 0.7～2.7m
3/ h; For powder speed is 0.5～4.0g/s; The carbonaceous material granularity is below 200 orders, and the residence time 4～8ms, the working pressure of system are normal pressure.
6,, it is characterized in that the carbonaceous material that uses is raw coal, carbon materials, rubber tyre according to the preparation method of the described carbon nano-tube material of claim 1.
7,, it is characterized in that described catalystic material comprises micron order and nano level Al, Ca, Cu, Mn according to the preparation method of the described carbon nano-tube material of claim 1, Ni, Pt, Fe, Co, La, W, Au, the Pd metal also comprises micron order and nanosize metal oxide LaO, Al
2O
3, Mo
2O
5, TiO
2, Fe
2O
3, CuO and non-metal particle Si, SiO
2
8,, it is characterized in that the employed metal electrode material of plasma generator is Al, Ca, Cu, Mn according to the preparation method of the described carbon nano-tube material of claim 1, Ni, Pt, Fe, Co, La, W, Au, the Pd metallic substance, and with the preparation-obtained alloy electrode of these materials.
9,, it is characterized in that the hybrid mode of carbonaceous material and catalyzer is according to the preparation method of the described carbon nano-tube material of claim 1: I, before spraying, carbonaceous material and micron order catalyzer are directly mixed, mixture is done
For raw material directly sprays among the plasma jet, or II, micron order catalyzer and carbonaceous material be by different position stream penetratings, the catalyzer spray
The implantation site sprays into 20～50mm on the position at coal dust, or III, carbonaceous material is directly sprayed into, and simultaneously directly and the generation of electric arc splash-proofing sputtering metal electrode receive
The meter level catalyzer mixes in jet.
10, realize the device of the described carbon nano-tube material preparation of claim 1, it is characterized in that: primary device is by plasma generator (1), feeder (2), reactor (3), several parts of collector (4) are formed, auxiliary unit has for powder part (8), supplying unit (10) and air path part: hydrogen source gas (5), argon gas origin (6), for powder gas circuit (7) and balance gas circuit (9), from top to bottom, the order of connection of primary device is arc plasma generator (1), feeder (2), reactor (3), collector (4), the exit diameter of arc plasma generator (1) is 10～20mm, feeder (2) tightly is positioned under the arc plasma generator (1), feeder (2) centre portions is the plasma jet passage of diameter at 10～30mm, the jet that is come out by arc plasma generator (1) is from passing through here, it is the feed nozzle of 3～5mm that feeder (2) has two diameters, the vertical range of first nozzle distance arc plasma generator (1) jet exit is 15mm, the vertical range of second nozzle distance arc plasma generator (1) jet exit is 35～65mm, pass through nozzle, catalyzer and carbon compound can be directly by among the stream penetratings, and then under the feeder reactor (3), reactor (3) is a tubular structure, diameter is 10～30mm, and length is 300～350mm.
Priority Applications (1)
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|---|---|---|---|
| CN01122772A CN1093507C (en) | 2001-07-22 | 2001-07-22 | Preparation of carbon nanometer pipe material and its equipment |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN01122772A CN1093507C (en) | 2001-07-22 | 2001-07-22 | Preparation of carbon nanometer pipe material and its equipment |
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| CN1328958A CN1328958A (en) | 2002-01-02 |
| CN1093507C true CN1093507C (en) | 2002-10-30 |
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Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA2385802C (en) * | 2002-05-09 | 2008-09-02 | Institut National De La Recherche Scientifique | Method and apparatus for producing single-wall carbon nanotubes |
| CA2505996A1 (en) * | 2002-11-15 | 2004-06-03 | Mcgill University | Method and apparatus for producing single-wall carbon nanotubes |
| CN100484869C (en) * | 2006-08-11 | 2009-05-06 | 中国科学院等离子体物理研究所 | Method for preparing carbon nano tube using high power plasma generator |
| CN101531362B (en) * | 2009-04-17 | 2010-11-10 | 北京化工大学 | Method for one-step growth of carbon nanotube by taking carbon composite as catalyst |
| CN106276846B (en) * | 2016-07-15 | 2018-02-23 | 华北电力大学 | A kind of system and method for preparing CNT |
| CN107275113B (en) * | 2017-06-08 | 2019-12-13 | 中国科学院电工研究所 | method for preparing flexible supercapacitor composite electrode by using double-medium jet plasma |
| CN108927143B (en) * | 2018-09-06 | 2020-01-03 | 北京宝诺康医药科技有限公司 | Preparation method of pharmaceutical intermediate for treating open-angle glaucoma |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0761803A (en) * | 1993-08-26 | 1995-03-07 | Nec Corp | Production of fullerene and carbon nanotube |
| JPH11116218A (en) * | 1997-10-17 | 1999-04-27 | Osaka Gas Co Ltd | Production of single layered nanotube |
| CN1277935A (en) * | 1999-06-16 | 2000-12-27 | 中国科学院金属研究所 | Method for preparing single wall nanometer carbon tube hydrogen storage material |
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2001
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0761803A (en) * | 1993-08-26 | 1995-03-07 | Nec Corp | Production of fullerene and carbon nanotube |
| JPH11116218A (en) * | 1997-10-17 | 1999-04-27 | Osaka Gas Co Ltd | Production of single layered nanotube |
| CN1277935A (en) * | 1999-06-16 | 2000-12-27 | 中国科学院金属研究所 | Method for preparing single wall nanometer carbon tube hydrogen storage material |
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