CN110616080A

CN110616080A - Self-sintering carbon material process technology

Info

Publication number: CN110616080A
Application number: CN201910976485.0A
Authority: CN
Inventors: 李建平
Original assignee: Zhejiang Kabon New Materials Co Ltd
Current assignee: Zhejiang Kabon New Materials Co Ltd
Priority date: 2019-10-15
Filing date: 2019-10-15
Publication date: 2019-12-27
Anticipated expiration: 2039-10-15
Also published as: CN110616080B

Abstract

The invention belongs to the technical field of materials, and particularly relates to a process technology for self-sintering a carbon material. The invention prepares the carbon material with higher self-sintering function by carrying out specific heating and crushing on the selected fixed asphalt so as to be used for manufacturing high-density carbon products. The invention has the advantages of reasonable, effective, simple and economic preparation process of the carbon material, good self-sintering function of the prepared carbon material, and large density and bonding strength of the carbon product obtained from the carbon material.

Description

Self-sintering carbon material process technology

Technical Field

The invention belongs to the technical field of materials, and particularly relates to a process technology for self-sintering a carbon material.

Background

Carbon products, as a new material, have not only chemical stability but also high strength, high temperature resistance, corrosion resistance and other advantages, and are therefore widely used in the industrial field.

The traditional carbon products are manufactured by complex processes, including a hot mixing process for preparing a binder by a filler-binder method, an extrusion molding process, and a sintering process for densification and carbonization.

In addition, high temperature crystallization, particle size, packing density, surface properties, etc. are important factors in addition to binding properties, and generally, it is desirable that the raw material for producing the carbon product have a small and uniform particle size.

Currently available methods, such as a production process of calcining a filler-binder mixture having a needle-like structure and a softening point of about 100 ℃, without using an agglomeration additive, produce Medium Carbon Microspheres (MCMB) for producing carbon products by a method of preparing spherical liquid crystal materials by separating them with a solvent generated during heating of pitch.

However, the above-mentioned method for preparing MCMB has problems of long production time, complicated process, and maximum weight of not more than 30%, and thus lacks economical practicality.

Korean laid-open publication No. 10-2000-0041945 discloses a process for producing medium carbon microbeads. Disclosed is a method for producing asphalt having a high content of Toluene Insolubles (TI) through a first heat treatment process (air blowing method) and securing its caking property as a hydrogen donor compound through a second heat treatment process, but in this method, the content of TI is only 48.8-66.7%, and a complicated and time-consuming process is still required.

Another technique disclosed in korean laid-open publication No. 10-1997-027014 relates to a method of manufacturing a carbon-carbon product by subjecting pitch having a softening point of 280 ℃ or higher to a heat treatment process without using a binder additive, and then pulverizing to 100 μm and oxidizing the surface with oxygen, but in this method, there are problems of poor self-sintering property of the carbon product material and high production cost.

Disclosure of Invention

The invention aims to provide a self-sintering carbon material process technology which can prepare a carbon material with higher self-sintering function by carrying out specific heating and crushing on selected fixed asphalt for manufacturing a high-density carbon product. The invention has the advantages of reasonable, effective, simple and economic preparation process of the carbon material, good self-sintering function of the prepared carbon material, and large density and bonding strength of the carbon product obtained from the carbon material.

The technical scheme adopted by the invention for solving the problems is as follows: the carbon material with self-sintering function has quinoline insoluble matter in 88-92 wt% and beta resin in 7-12 wt% and average grain size of 0.5-5 micron.

In the present invention, any material capable of obtaining a carbon solid by a heat treatment may be used as a raw material for preparing the carbonaceous material.

In addition, the β resin means a component insoluble in toluene but soluble in quinoline, that is, β resin content (%) = toluene insoluble content (TI) -quinoline insoluble content (QI), and β resin content is an important factor determining self-sintering property, and the resin component has adhesion and is a highly efficient component converted into solid carbon by reaction during heat treatment, so that a suitable β resin component is a key component having high-strength self-sintering property, and if the β resin content is too low, the product has no self-sintering property, and if the β resin content is too high, the finally produced carbon molded product is easily swollen or cracked, so that the β resin content in the range of 7 to 12% is the most stable choice, and the above two problems can be effectively avoided.

Also, when the average particle size of the carbonaceous material is less than 0.5. mu.m, the step of preparing the carbonaceous material by itself by pulverization is problematic in that it is cumbersome and time-consuming, whereas when the average particle size is more than 5. mu.m, the carbon molded article produced is insufficient in density and insufficient in blocking, and therefore, the average particle size range of 0.5 to 5 μm is most preferable.

The further preferred technical scheme is as follows: the diameter of the carbon material at the middle position in an X-ray diffraction test is 0.35-0.38nm, and the liquid crystal value in the c-axis direction is 0.64-0.66 nm.

The further preferred technical scheme is as follows: the carbon material maintains optical isotropy at a temperature of at least 2500 ℃.

The further preferred technical scheme is as follows: the average particle size of the carbon material is 5 μm.

The further preferable technical scheme is that the method sequentially comprises the following steps:

s1, heating and preserving heat of the solid asphalt,

s2, stirring the product obtained in the step S1 under negative pressure;

and S3, cooling and crushing the product obtained in the step S2 to obtain the final carbon material product.

The further preferred technical scheme is as follows: in step S1, the softening point of the solid asphalt is 110-.

In the invention, if the heating temperature is lower than 450 ℃, the problem of large heating preparation time consumption exists, and if the heating temperature is higher than 600 ℃, the problems that the consistency of the produced carbon material is poor and the content of beta resin does not reach the standard exist, so that the heating temperature of 450-600 ℃ is selected to ensure the whole preparation effect.

The further preferred technical scheme is as follows: in step S1, the solid pitch has a softening point of 110 ℃.

The further preferred technical scheme is as follows: in step S1, the heating temperature is 470-550 ℃.

The further preferred technical scheme is as follows: in step S2, protective inert gas is introduced during the stirring process, and the stirring speed is 40-100 rpm.

The further preferred technical scheme is as follows: in step S3, the carbon material product is used to manufacture a high-density carbon product.

Drawings

FIG. 1 is a graph showing the results of measuring the quinoline insolubles and the beta resin contents of the carbon materials in comparative examples 1 to 3 of the present invention.

FIG. 2 is a scanning electron micrograph of a fracture plane of the molded article in comparative examples 1 to 3 of the present invention, showing a large number of cracks and pores, which are not suitable for the production of carbon products.

FIG. 3 is a graph showing the results of measuring the X-ray diffraction diameter d (002) and the liquid crystal value of the carbon material in comparative examples 4 to 5 of the present invention.

FIG. 4 is a scanning electron micrograph of a fracture plane of the molded article in comparative examples 4 to 5 of the present invention, showing a large number of cracks and pores, which are not suitable for the production of carbon products.

FIG. 5 is a graph showing the results of measuring the quinoline insolubles and the β resin contents of the carbon materials in examples 1 to 5 of the present invention.

FIG. 6 is a graph showing the results of measuring the X-ray diffraction diameter d (002) and the liquid crystal value of the carbon material in examples 1, 3 and 5 of the present invention.

FIG. 7 is a scanning electron micrograph of the fracture plane of the molded article of examples 1-5 of the present invention showing dense and high adhesion, suitable for the production of carbon products.

Detailed Description

The following description is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention.

Comparative examples 1 to 3

As shown in FIGS. 1 and 2, coal-based asphalt having a softening point of 110 ℃ was charged into an SUS reactor, and then heated to 400 ℃, 430 ℃ and 450 ℃ for 5 hours, 3 hours and 2 hours, respectively. During the heat treatment, the stirring speed was 50rpm, the inside of the reactor was uniformly heated, nitrogen was flowed during the reaction, the inert atmosphere was maintained, and the negative pressure state was maintained, to prevent the generation of the internal pressure of the gas component generated in the reaction system. After a certain time, the product is taken out of the reactor and cooled, thus obtaining the heat-treated product. The component analysis of the heat-treated product shows that the insoluble quinoline content is too low and the beta resin content is too high, which does not meet the parameter index of the carbon material, as shown in figure 1.

In addition, in order to confirm the self-sintering function of the carbonaceous material product obtained by the heat treatment, a carbonaceous material having an average particle size of 5 μm was prepared under a molding pressure of 300kg/㎠ using a metal mold in an inert atmosphere, and the fracture surface of the carbonaceous product was observed by a Scanning Electron Microscope (SEM), and as a result, as shown in fig. 2, the carbonaceous product had a large number of cracks and pores and was not suitable for the production of the carbonaceous product.

Comparative examples 4 to 5

As shown in FIGS. 3 and 4, after charging the petroleum-based asphalt having a softening point of 120 ℃ into the SUS-made reactor, the temperature was increased to 400 ℃ and 450 ℃ respectively, and maintained for 3 hours and 2 hours, respectively. During the heat treatment, the stirring speed was 50rpm, the inside of the reactor was uniformly heated, and during the reaction, a mixed gas having an oxygen content of 50ppm was flowed, and an inert atmosphere was maintained, and a negative pressure state was maintained, to prevent the generation of an internal pressure of a gas component generated in the reaction system. After a certain time, the product is taken out of the reactor and cooled, thus obtaining the heat-treated product. XRT analysis of the heat-treated product showed that the diameter of the product was too large and the liquid crystal value was too small in the X-ray diffraction test, which was not in accordance with the parameter index of the carbon material, as shown in FIG. 3.

In addition, in order to confirm the self-sintering function of the carbonaceous material product obtained by the heat treatment, a carbonaceous material having an average particle size of 5 μm was prepared under a molding pressure of 300kg/㎠ using a metal mold in an inert atmosphere, and the fracture surface of the molded article was observed by a Scanning Electron Microscope (SEM), and as a result, as shown in fig. 4, the carbonaceous product had a large number of cracks and pores and was not suitable for the production of the carbonaceous product.

Examples 1 to 5

As shown in FIGS. 5, 6 and 7, after charging coal-based asphalt having a softening point of 110 ℃ into an SUS reactor, the temperature was raised to 470 ℃, 490 ℃, 500 ℃, 530 ℃ and 550 ℃ for 1 hour or 2 hours, respectively. In the heat treatment process, the stirring speed is 50rpm, so that the interior of the reactor is uniformly heated, nitrogen flows in the reaction process, the inert atmosphere is kept, the negative pressure state is kept, and the gas component generated by the reaction system is prevented from generating internal pressure. After a period of time, it is removed from the reactor and cooled to obtain a heat treated product. The results of the component analysis of the heat-treated product are shown in fig. 5 and fig. 6, wherein the quinoline insoluble content, the beta resin content, the diameter d (002) in the X-ray diffraction test and the liquid crystal value all meet the parameter indexes of the carbon material.

In addition, in order to confirm the self-sintering function of the carbonaceous material product obtained by the heat treatment, a carbonaceous product was prepared by using a carbonaceous material having an average particle size of 5 μm under a molding pressure of 300kg/㎠ in an inert atmosphere using a metal mold, and the fracture surface of the molded article was observed by a Scanning Electron Microscope (SEM), and as shown in fig. 7, the carbonaceous product had a high density and a high binding capacity and was suitable for the production of the carbonaceous product.

In conclusion, the carbon material of the present invention has the advantages of caking components and good self-sintering property, and can be suitably used for the production of carbon molded products without adding other binders.

While the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various modifications can be made within the knowledge of those skilled in the art without departing from the spirit of the present invention. These are non-inventive modifications, which are intended to be protected by patent laws within the scope of the claims appended hereto.

Claims

1. The self-sintering carbon material process technology is characterized in that: the weight percentage of quinoline insoluble substances in the carbon material is 88-92%, the weight percentage of beta resin is 7-12%, and the average particle size range is 0.5-5 μm.

2. The self-sintering carbon material process technology of claim 1, characterized in that: the diameter of the carbon material at the middle position in an X-ray diffraction test is 0.35-0.38nm, and the liquid crystal value in the c-axis direction is 0.64-0.66 nm.

3. The self-sintering carbon material process technology of claim 1, characterized in that: the carbon material maintains optical isotropy at a temperature of at least 2500 ℃.

4. The self-sintering carbon material process technology of claim 1, characterized in that: the average particle size of the carbon material is 5 μm.

5. The self-sintering carbon material process technology of claim 1, characterized by comprising the following steps in sequence:

s1, heating and insulating solid asphalt;

s2, stirring the product obtained in the step S1 under negative pressure;

6. The self-sintering carbon material process technology of claim 5, characterized in that: in step S1, the softening point of the solid asphalt is 110-.

7. The self-sintering carbon material process technology of claim 5, characterized in that: in step S1, the solid pitch has a softening point of 110 ℃.

8. The self-sintering carbon material process technology of claim 5, characterized in that: in step S1, the heating temperature is 470-550 ℃.

9. The self-sintering carbon material process technology of claim 5, characterized in that: in step S2, protective inert gas is introduced during the stirring process, and the stirring speed is 40-100 rpm.

10. The self-sintering carbon material process technology of claim 5, characterized in that: in step S3, the carbon material product is used to manufacture a high-density carbon product.