CN110685039B

CN110685039B - Method for producing carbon nano tube fibers in batch

Info

Publication number: CN110685039B
Application number: CN201910947999.3A
Authority: CN
Inventors: 秦磊; 陈逗鸿; 弓晓晶; 罗鲲; 李亚利
Original assignee: Changzhou University
Current assignee: Changzhou University
Priority date: 2019-10-08
Filing date: 2019-10-08
Publication date: 2022-03-25
Anticipated expiration: 2039-10-08
Also published as: CN110685039A

Abstract

The invention belongs to the technical field of nanofiber preparation, and particularly relates to a method for producing carbon nanotube fibers in batches. A large quartz tube with a honeycomb structure in a quartz tube or a small quartz tube sleeved in the large quartz tube is used as a reaction chamber, a mixed solution of a carbon source, a catalyst, an accelerant and water is injected into carrier gas airflow through a micro injection pump or an atomizer, the carrier gas airflow enters the quartz tube under the driving of the airflow, the solution is vaporized and then cracked into atoms, the cracked atoms enter the honeycomb inner/small quartz tubes of the quartz tube under the driving of the airflow, carbon nanotube aerogel with a cylindrical structure is generated in each honeycomb inner/small quartz tube respectively, and the cylindrical structure gel is pulled out of the quartz tube to pass through water through mechanical winding to obtain continuous carbon nanotube fibers. The fiber prepared by the invention has the advantages of thin diameter and low linear density; the fiber quality is increased, and the yield is improved; the strength is higher, and the performance is better; can be used for mass production of carbon nanotube fibers.

Description

Method for producing carbon nano tube fibers in batch

Technical Field

The invention belongs to the technical field of nanofiber preparation, and particularly relates to a method for producing carbon nanotube fibers in batches.

Background

Since the discovery of carbon nanotubes, CNTs have attracted a great deal of interest to experts in different fields in the scientific community, with their unique one-dimensional tubular structure, excellent electrical properties, extremely high thermal conductivity, good thermal and chemical stability, and low density. However, to more broadly and fully exploit the excellent properties of CNTs, it is necessary to assemble the CNTs into macroscopic structures, such as fibers, films, and the like.

The preparation of carbon nanotube fiber by high temperature chemical vapor deposition is the most stable preparation method at present, and the chemical vapor deposition method can be used for producing continuous carbon nanotube fiber, and is a method capable of industrially preparing fiber. Chinese patent CN103628183A discloses a method for producing carbon nanotube fibers in large scale by multi-furnace series connection and multi-furnace simultaneous stable continuous spinning, but the preparation method adopts multi-furnace series connection, thereby greatly improving the production cost.

Disclosure of Invention

The invention provides a method for producing carbon nanotube fibers in batches, which can overcome the defects of the prior art and realize the batch production of the carbon nanotube fibers. And the method saves energy and reduces production cost.

The invention is realized by the following technical scheme.

A large quartz tube with a honeycomb structure or a small quartz tube sleeved in the large quartz tube is used as a reaction chamber to prepare large-batch carbon nanotube fibers.

Injecting a mixed solution of a carbon source, a catalyst, an accelerant and water (wherein the carbon source is 96.5 percent, the catalyst is 1 percent, the accelerant is 0.5 percent and the water is 2 percent) into carrier gas flow by using a micro-injection pump or an atomizer, reacting in a synthesis reactor (namely a large quartz tube with a honeycomb structure or a quartz tube with a small quartz tube sleeved in the large quartz tube), completing vaporization and cracking of the mixed solution in an area A of the large quartz tube to generate white aerogel-like fog clusters, driving the white aerogel-like fog clusters to enter the small quartz tube or a honeycomb under the drive of the carrier gas flow to generate black semitransparent cylindrical carbon nanotube aerogel in an area B of the small quartz tube or the honeycomb, then extending a mechanical arm into the small quartz tube from a water tank, switching on a power supply, rotating the front end of the mechanical arm, adhering the black semitransparent cylindrical carbon nanotube aerogel on the mechanical arm, mechanically winding, and mechanically winding, and then, withdrawing the mechanical arm, or manually stretching an iron wire into the small quartz tube from the water tank, pulling the black semitransparent cylindrical carbon nanotube aerogel out of the small quartz tube and passing through the water tank, shrinking the black semitransparent cylindrical carbon nanotube aerogel into carbon nanotube fibers, and winding the fibers on a spinning shaft through a yarn guide roller to form a coil so as to obtain the continuous carbon nanotube fibers.

Or the white aerogel-shaped foggy mass generated after cracking enters a honeycomb structure in the quartz tube under the driving of air flow, black semitransparent cylindrical carbon nanotube aerogel is generated in each honeycomb respectively, then a mechanical arm or a manual iron wire is stretched into the honeycomb of the quartz tube, the black semitransparent cylindrical carbon nanotube aerogel is wound, the carbon nanotube aerogel is pulled out, and the carbon nanotube fiber is formed by water densification.

The specific process comprises the following steps: a mixed solution consisting of 96.5 percent of carbon source, 1 percent of catalyst, 0.5 percent of accelerant and 2 percent of water is vaporized by a nozzle (6) at 180 ℃ under the pushing action of a micro-injection pump (1) and then enters a large quartz tube (2) along with carrier gas, the cracking (400-, and then, the mechanical arm (12) is stretched into the quartz tube from the water tank (11), a power supply is switched on, the front end of the mechanical arm rotates to adhere the black semitransparent cylindrical carbon nanotube aerogel on the mechanical arm for mechanical winding, after the mechanical winding, the mechanical arm is withdrawn, or an iron wire is manually stretched into the small quartz tube from the water tank, after the black semitransparent cylindrical carbon nanotube aerogel is pulled out of the small quartz tube or passes through the water tank by a honeycomb, the cylindrical carbon nanotube aerogel is contracted into carbon nanotube fibers, and then the fibers are wound on a spinning shaft (5) through a guide wire roller (10) to be wound into a coil, so that continuous carbon nanotube fibers are obtained. Similarly, each small quartz tube or honeycomb can obtain continuous carbon nanotube fibers, thereby realizing mass production of the carbon nanotube fibers.

The diameter of the large quartz tube is 80-300mm, the diameter of the small quartz tube or the honeycomb is 20-80mm, and at least 3 small quartz tubes or three honeycombs can be sleeved in the large quartz tube, so that the mass production is realized.

The vertical tubular resistance furnace used in the method is of a three-temperature-zone structure, namely the resistance furnace is divided into three temperature zones from top to bottom, namely an upper temperature zone, a middle temperature zone and a lower temperature zone, the temperature of the upper temperature zone can be adjusted to be low, the temperature of the middle temperature zone and the temperature of the lower temperature zone are higher, and the temperature difference between the zone A and the zone B is realized.

The temperature of the resistance furnace is set before the experiment, the temperature of each point in the quartz tube is measured by a thermocouple after the tube type resistance furnace (3) is empty-burned, the length of the small quartz tube is selected according to the test temperature, the used small quartz tubes are different in length but consistent in tail end, the quartz tubes with different lengths can be properly selected according to the temperature to achieve the purpose of regulating and controlling the front end position of the quartz tube so as to meet the reaction condition, and then the tail end of the small quartz tube is fixed on the water tank through the flange plate.

Or the quartz tube is installed and fixed before the experiment, the temperature of each point in the quartz tube is measured by a thermocouple after the quartz tube is empty-burned, and then the temperature of each temperature zone (upper, middle and lower) is regulated and controlled to achieve the purpose of controlling the reaction condition.

The temperature in the small quartz tube or the honeycomb is controlled to be 800-1300 ℃, preferably 1050-1300 ℃, so that the cylindrical carbon nanotube aerogel can be formed.

The front end of the small quartz tube or the honeycomb is not higher than 800 ℃ and not lower than 400 ℃ so as to ensure that the mixed solution is fully cracked and prevent atoms cracked by the mixed solution from being assembled into the carbon nano tube aerogel before entering the small quartz tube or the honeycomb.

The rear end of the small quartz tube or the honeycomb is parallel to the rear end of the furnace body, and the tail end of the small quartz tube and the tail end of the large quartz tube are fixed on the water tank through a flange plate.

The carbon source is hydrocarbon gas, carbon-containing organic matter or mixed carbon source. Hydrocarbon gases including carbon monoxide, methane, ethane, ethylene, propylene, acetylene, and the like; the carbon-containing organic substance comprises methanol, ethanol, diethyl ether, benzene, xylene, n-hexane, etc. The mixed carbon source comprises the mixing of hydrocarbon gas, the mixing of hydrocarbon gas and carbon-containing organic matter and the mixing of carbon-containing organic matter.

The catalyst is organic or inorganic metal salt of Fe, Co, Ni, Cu, Au, etc and includes ferrocene, cobaltocene, nickelocene, ferric chloride, ferric sulfide, nickel oxalate, cobalt oxalate, copper chloride, etc.

The accelerators include thiophene, water, hydrogen sulfide, carbon disulfide, and the like, or mixtures thereof.

The carrier gas is hydrogen, argon, nitrogen, helium or the mixture of a plurality of gases, and the carrier gas flow is 400-2000 ml/min.

The invention relates to a device for mass production of carbon nano tube fibers, which comprises a micro-injection pump (1), a large quartz tube (2), a tubular resistance furnace (3), a sealing box (4), a nozzle (6), a small quartz tube/honeycomb (8), a water tank (11) and a mechanical arm (12), the nozzle (6) with the micro-injection pump (1) is sequentially connected with the large quartz tube (2) from top to bottom through the front end sealing flange (7), the large quartz tube (2) is installed inside the tubular resistance furnace (3), the small quartz tube/honeycomb (8) is arranged inside the large quartz tube (2), the tail end of the large quartz tube (2) is connected with the sealing box (4) through the rear end sealing flange (9), the lower part of the sealing box (4) is provided with the water tank (11), the water tank (11) is internally provided with the yarn guide roller (10), and the spinning shaft (5) and the mechanical arm (12) are arranged outside the water tank (11).

Has the advantages that:

the invention provides a method for producing carbon nanotube fibers in batches, which adopts a device with a large quartz tube with a honeycomb structure or a small quartz tube sleeved in the large quartz tube to prepare large batches of carbon nanotube fibers, removes a liquid injection system which is increased because the quartz tubes are arranged side by side, reduces the use of a tubular resistance furnace, reduces the production cost and energy consumption, and is suitable for industrialized batch production of the carbon nanotube fibers. The prepared fiber has high strength, low linear density and low fiber diameter.

Drawings

FIG. 1 is a schematic view of a reaction apparatus before modification, which is a vertical tube reactor, wherein 1, a micro-injection pump, 2, a quartz tube, 3, a tube-type resistance furnace, 4, a seal box, 5, a spindle, 6, a nozzle, 7, a front end seal flange, 8, a rear end seal flange 9, a guide roller, 10, a water tank, 11 and a mechanical arm;

fig. 2 is a schematic diagram of a reaction apparatus adopted in the present invention (a schematic diagram of an apparatus in which a large quartz tube is sleeved with a small quartz tube), the apparatus being a vertical tube reactor, wherein 1, a micro-injection pump, 2, a large quartz tube, 3, a tube-type resistance furnace, 4, a seal box, 5, a spindle, 6, a nozzle, 7, a front end seal flange, 8, a small quartz tube, 9, a rear end seal flange 10, a guide roller, 11, a water tank, 12, and a robot arm;

fig. 3 is a schematic view of a reaction apparatus (a schematic view of a large quartz tube apparatus having a honeycomb structure) adopted in the present invention, wherein 1, a micro-injection pump, 2, a large quartz tube, 3, a tube-type resistance furnace, 4, a seal box, 5, a spindle, 6, a nozzle, 7, a front end seal flange, 8, a honeycomb, 9, a rear end seal flange 10, a guide wire roller, 11, a water tank, 12, and a robot arm;

FIG. 4 is a schematic diagram of the distribution of the temperature zone of the tubular resistance furnace;

FIG. 5 is a schematic diagram of the preparation of carbon nanotube fibers;

FIG. 6 is a photograph of a prepared carbon nanotube fiber;

FIG. 7 is a diameter of a carbon nanotube fiber before modification of the device;

fig. 8 shows the diameter of the carbon nanotube fiber after the device modification.

Detailed Description

When the carbon nano tube fiber is prepared, the water level in the water tank is higher than that of the sealing tank so as to ensure the sealing of the vertical tube type reactor.

The specific process comprises the following steps: the mixed solution is vaporized by a nozzle under the pushing action of a micro-injection pump and enters a reactor along with a carrier gas, white aerogel-like fog groups (aerogel consisting of atoms cracked from reaction liquid, like a group of smoke) are generated by cracking in an area A, the white aerogel-like fog groups enter a small quartz tube or a honeycomb under the driving of carrier gas flow, black semitransparent cylindrical carbon nanotube aerogel is generated in a small quartz tube or honeycomb area B, the black semitransparent cylindrical carbon nanotube aerogel moves towards the tail end of the quartz tube under the driving of the gas flow, the black semitransparent cylindrical carbon nanotube aerogel is pulled out of the quartz tube by mechanical winding, water is compacted into fibers, and the fibers are wound into coils through a guide wire roller and a spinning shaft, so that continuous carbon nanotube fibers are obtained. Similarly, each small quartz tube can obtain continuous carbon nanotube fibers, thereby realizing mass production of the carbon nanotube fibers.

Nothing in this specification is said to apply to the prior art.

Example 1

The experimental apparatus shown in FIG. 2 was used as a high temperature reactor, in which a large quartz tube was fitted inside three small quartz tubes. Ethanol is used as a carbon source, ferrocene is used as a catalyst, thiophene is used as an accelerant, and hydrogen is used as carrier gas to prepare the carbon nanotube fiber.

50g of ethanol, 0.50g of ferrocene, 0.28g of thiophene and 1g of water are dispersed and mixed by ultrasonic, and then are placed into a micro-syringe and are arranged at one end of a reactor. Introducing hydrogen into a large quartz tube (2), adjusting the upper furnace temperature of a tubular resistance furnace (3) to 500 ℃, adjusting the middle and lower furnace temperatures to 1170 ℃, injecting a mixed solution in an injector into the large quartz tube at the rate of 13.3ml per hour by using a micro-injection pump (1), cracking in an area A to generate white aerogel-like fog clusters, driving the white aerogel-like fog clusters to enter a small quartz tube or a honeycomb under the driving of carrier gas flow, generating black semitransparent cylindrical carbon nanotube aerogel in a small quartz tube or a honeycomb area B, moving the black semitransparent cylindrical carbon nanotube aerogel to the tail end of the quartz tube under the driving of the gas flow, extending a mechanical arm (12) into the small quartz tube from a water tank (11), switching on a power supply, rotating the front end of the mechanical arm, adhering the black semitransparent cylindrical carbon nanotube aerogel on the mechanical arm for mechanical winding, withdrawing the mechanical arm after mechanical winding, after the black semitransparent cylindrical carbon nanotube aerogel is pulled out of a small quartz tube and passes through a water tank, the black semitransparent cylindrical carbon nanotube aerogel shrinks into carbon nanotube fibers, and then the fibers are wound on a spinning shaft (5) through a guide roller (10) and are wound into coils to respectively obtain three coils of fibers. The mass of three rolls of fiber was weighed with an analytical balance, which increased the mass of the fiber by 2.5 times compared to before modification. (the fiber mass before modification was 0.21g, and the fiber mass obtained after modification was 0.53 g.)

Example 2

An experimental apparatus as shown in fig. 3 was used, and a large quartz tube having a honeycomb structure, in which the number of honeycombs was 5, was used as a high-temperature reactor. Ethanol is used as a carbon source, ferrocene is used as a catalyst, thiophene is used as an accelerant, and hydrogen is used as carrier gas to prepare the carbon nanotube fiber.

The procedure of example 1 was followed, 50g of ethanol, 0.50g of ferrocene, 0.28g of thiophene and 1g of water were ultrasonically dispersed and mixed, and the mixture was placed in a microinjector and installed at one end of a reactor. Introducing hydrogen into a large quartz tube (2), adjusting the upper furnace temperature of a tubular resistance furnace (3) to 500 ℃, adjusting the middle and lower furnace temperatures to 1170 ℃, injecting a mixed solution in an injector into the large quartz tube at the rate of 13.3ml per hour by using a micro-injection pump (1), cracking in an area A to generate white aerogel-like fog clusters, driving the white aerogel-like fog clusters to enter a small quartz tube or a honeycomb under the drive of carrier gas flow, generating black semitransparent cylindrical carbon nanotube aerogel in a small quartz tube or a honeycomb area B, moving the black semitransparent cylindrical carbon nanotube aerogel to the tail end of the quartz tube under the drive of the gas flow, extending a mechanical arm (12) into the quartz tube from a water tank (11), switching on a power supply, rotating the front end of the mechanical arm, adhering the black semitransparent cylindrical carbon nanotube aerogel on the mechanical arm for mechanical winding, withdrawing the mechanical arm after mechanical winding, after the black semitransparent cylindrical carbon nanotube aerogel is pulled out of a small quartz tube and passes through a water tank, the black semitransparent cylindrical carbon nanotube aerogel shrinks into carbon nanotube fibers, and then the fibers are wound on a spinning shaft (5) through a guide roller (10) and are wound into coils to respectively obtain five coils of fibers. The total mass of the fibers was increased by 30% compared to example 1 after weighing with an analytical balance.

Example 3

The procedure of example 1 was followed, the catalyst was changed to cobaltocene, the reaction was carried out under these conditions, formation of continuous carbon nanotube fibers was observed, and the mass of the fibers was measured and was comparable to that of example 1.

Example 4

The procedure of example 1 was the same as that of example 1, the furnace temperature was lowered to 1000 ℃, the reaction was carried out under the conditions, formation of carbon nanotube fibers was observed, and the mass thereof was measured to be 0.49g, and the fibers obtained were reduced as compared with example 1.

Example 5

The diameter of the carbon nanotube fiber obtained in example 1 was reduced from 140um to about 100um by using a polarizing microscope measuring device of the model Shunhua CX40P, and the diameter of the carbon nanotube fiber obtained before and after the modification was reduced by 25%. The specific optical microscope photographs are shown in fig. 6 and fig. 7.

Example 6

The carbon nanotube fiber obtained in example 1 was selected, and the linear density of the carbon nanotube fiber obtained before and after the modification was performed by an XQ-1 type fiber fineness measuring apparatus, and the linear density of the obtained fiber was reduced from 0.5Tex to 0.3Tex (the linear density means the mass of the fiber per unit length).

Example 7

The carbon nanotube fiber obtained in example 1 was selected and the strength of the carbon nanotube fiber obtained before and after the modification by the Asahi fiber tensile tester was increased from 120MPa to 175MPa, which was 50% higher.

Comparative example 1

An experimental set-up as shown in figure 1 was used (before modification). Ethanol is used as a carbon source, ferrocene is used as a catalyst, thiophene is used as an accelerant, and hydrogen is used as carrier gas to prepare the carbon nanotube fiber.

50g of ethanol, 0.50g of ferrocene, 0.28g of thiophene and 1g of water are dispersed and mixed by ultrasonic, and then are placed into a micro-syringe and are arranged at one end of a reactor. Introducing hydrogen into the quartz tube (2) at a gas flow rate of 900ml/min, adjusting the temperature of the upper furnace, the middle furnace and the lower furnace of the tubular resistance furnace (3) to 1170 ℃, injecting the mixed solution in the injector into the quartz tube at a rate of 13.3ml per hour by using a micro-injection pump (1), vaporizing the solution firstly, then cracking to form atoms, black semitransparent cylindrical carbon nano tube aerogel is formed at high temperature and moves towards the tail end of the quartz tube under the push of air flow, then the mechanical arm (11) extends into the quartz tube from the water tank (10), the power supply is switched on, the front end of the mechanical arm rotates, the black semitransparent cylindrical carbon nanotube aerogel is adhered to the mechanical arm for mechanical winding, after the mechanical winding, then the mechanical arm is retracted, the black semitransparent cylindrical carbon nano tube aerogel is pulled out of the quartz tube and passes through the water tank, the carbon nano tube aerogel shrinks into carbon nano tube fibers, and then the fibers are wound on a spindle (5) to be coiled through a guide roller (9).

After being weighed by an analytical balance, the fiber mass is 0.21g, the fiber diameter is 140um, the fiber linear density is 0.5Tex, and the fiber strength is 120 MPa.

Claims

1. A method for mass production of carbon nanotube fibers is characterized in that a large quartz tube with a honeycomb structure in the quartz tube or a small quartz tube sleeved in the large quartz tube is used as a reaction chamber, a mixed solution consisting of a carbon source, a catalyst, an accelerant and water is injected into carrier gas flow through a micro-injection pump or an atomizer, the mixed solution enters the quartz tube under the drive of airflow, the mixed solution is vaporized and cracked in the area A of the large quartz tube to generate white aerogel-like fog mass, the white aerogel-like fog mass enters the small quartz tube or the honeycomb under the drive of carrier gas airflow, generating black semitransparent cylindrical carbon nanotube aerogel in a small quartz tube or a honeycomb area B, then stretching a mechanical arm or manually into a honeycomb of the quartz tube or the small quartz tube by using an iron wire, winding the cylindrical carbon nanotube aerogel, drawing the cylindrical carbon nanotube aerogel out, and carrying out water densification to form carbon nanotube fibers;

the cracking temperature of the area A is 400-800 ℃; the temperature for generating the black semitransparent cylindrical carbon nanotube aerogel in the region B is 800-1300 ℃;

the device for producing the carbon nano tube fiber in batch comprises a micro-injection pump (1), a large quartz tube (2), a tubular resistance furnace (3), a sealing box (4), a nozzle (6), a small quartz tube/honeycomb (8), a water tank (11) and a mechanical arm (12), the nozzle (6) with the micro-injection pump (1) is connected with the large quartz tube (2) from top to bottom through the front end sealing flange (7), the large quartz tube (2) is installed inside the tubular resistance furnace (3), the small quartz tube/honeycomb (8) is arranged inside the large quartz tube (2), the tail end of the large quartz tube (2) is connected with the sealing box (4) through the rear end sealing flange (9), the lower part of the sealing box (4) is provided with the water tank (11), the water tank (11) is internally provided with the yarn guide roller (10), and the spinning shaft (5) and the mechanical arm (12) are arranged outside the water tank (11).

2. The method of mass producing carbon nanotube fiber according to claim 1, wherein the method is: a mixed solution consisting of 96.5 percent of carbon source, 1 percent of catalyst, 0.5 percent of accelerant and 2 percent of water is vaporized by a nozzle (6) at 180 ℃ under the pushing action of a micro-injection pump (1) and then enters a large quartz tube (2) along with carrier gas, white aerogel-like fog masses are generated by cracking in an area A, the white aerogel-like fog masses enter a small quartz tube (8) or a honeycomb (8) under the driving of carrier gas flow, black semitransparent cylindrical carbon nanotube aerogel is generated in a small quartz tube or a honeycomb area B and moves to the tail end of the quartz tube under the driving of the air flow, a mechanical arm (12) extends into the quartz tube from a water tank (11), a power supply is switched on, the front end of the mechanical arm rotates to adhere the black semitransparent cylindrical carbon nanotube aerogel on a mechanical arm for mechanical winding, the mechanical winding is carried out, the mechanical arm is withdrawn, or an iron wire is manually extended into the quartz tube from the water tank, after the black semitransparent cylindrical carbon nanotube aerogel is pulled out of a honeycomb or a small quartz tube and passes through a water tank, the black semitransparent cylindrical carbon nanotube aerogel is contracted into carbon nanotube fibers, and then the fibers are wound on a spinning shaft (5) through a guide roller (10) and are wound into coils to obtain continuous carbon nanotube fibers.

3. The method of mass production of carbon nanotube fiber according to claim 1, wherein the catalyst is a metal organic salt or an inorganic salt; the carbon source is carbon-containing gas, carbon-containing organic matter or mixed carbon source; the accelerator is thiophene, water, hydrogen sulfide, carbon disulfide or a mixture thereof; the carrier gas is hydrogen, argon, nitrogen, helium or the mixture thereof, and the carrier gas flow is 400-2000 ml/min.

4. The method of mass production of carbon nanotube fiber according to claim 3, wherein the catalyst is ferrocene, cobaltocene, nickelocene, ferric chloride, ferric sulfide, nickel oxalate, cobalt oxalate, copper chloride; the carbon-containing organic matter is methanol, ethanol, diethyl ether, benzene, xylene and n-hexane; the carbon-containing gas is a hydrocarbon mixed gas; the accelerant is thiophene.

5. The method of claim 1, wherein the temperature for forming the carbon nanotube aerogel in the region B is 1050-1300 ℃.

6. The method of mass production of carbon nanotube fiber according to claim 1, wherein the diameter of the large quartz tube is 80 to 300mm, and the diameter of the small quartz tube or the honeycomb is 20 to 80 mm.

7. The method of mass production of carbon nanotube fiber according to claim 1, wherein the small quartz tube or honeycomb is placed at a front end position temperature of not higher than 800 ℃ and not lower than 400 ℃; the rear end of the small quartz tube or the honeycomb is parallel to the rear end of the furnace body.

8. The method as claimed in claim 1, wherein the tubular resistance furnace (3) has a three-temperature zone structure, which is divided into an upper temperature zone, a middle temperature zone and a lower temperature zone, wherein the temperature of the upper temperature zone is 800 ℃ plus one temperature, and the temperature of the middle temperature zone and the lower temperature zone are 800 ℃ plus one temperature plus 1300 ℃.