Phenolic resin-based porous carbon and preparation method thereof

Abstract

The invention relates to the technical field of porous carbon materials, and provides phenolic resin-based porous carbon and a preparation method thereof. The phenolic resin-based porous carbon comprises the following raw material components in parts by weight: 85-100 parts of phenolic resin, 5-10 parts of a curing agent, 10-18 parts of a binder and 17-21 parts of urea, the phenolic resin comprises boron modified phenolic resin and epoxy vinyl modified phenolic resin. Through the technical scheme, the problem of small specific surface area of porous carbon in related technologies is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of porous carbon materials, and in particular to a phenolic resin-based porous carbon and a preparation method thereof. Background Art

[0002] In the field of materials science, porous carbon, as an adsorption material with highly developed pore structure and huge specific surface area, is widely used in many key fields such as water treatment, gas purification, catalyst carrier and supercapacitor electrode material. Its excellent adsorption performance and surface activity are mainly derived from its rich pore structure and high specific surface area, which enables porous carbon to interact with external substances efficiently, achieve adsorption and removal of various pollutants and catalytic promotion of chemical reactions.

[0003] Traditionally, carbonization of phenolic resin is one of the important methods for preparing porous carbon. Due to its unique molecular structure and abundant carbon sources, phenolic resin can form a carbon skeleton during high-temperature carbonization, and construct a certain pore structure by reasonably regulating process parameters. However, the existing methods for preparing porous carbon by carbonization of phenolic resin have many limitations. On the one hand, the specific surface area of ​​porous carbon prepared by conventional processes is often difficult to reach the ideal level, which limits its use in high-end application scenarios with demanding adsorption performance. For example, in some high-precision gas separation processes, porous carbon is required to have a higher specific surface area to achieve efficient and selective adsorption of specific gas molecules, and porous carbon prepared by traditional methods is difficult to meet this demand. On the other hand, the existing technology has limited ability to regulate the pore structure during the carbonization process, resulting in uneven pore distribution, which affects the stability and consistency of the overall performance of porous carbon.

[0004] In view of this, developing a phenolic resin-based porous carbon with a high specific surface area will have important practical significance. Summary of the invention

[0005] The invention provides a phenolic resin-based porous carbon and a preparation method thereof, which solves the problem of small specific surface area of ​​porous carbon in the related art.

[0006] The technical solution of the present invention is as follows: The present invention provides a phenolic resin-based porous carbon, wherein the raw materials include the following components in parts by weight: 85-100 parts of phenolic resin, 5-10 parts of curing agent, 10-18 parts of binder, and 17-21 parts of urea; The phenolic resin includes boron-modified phenolic resin and epoxy vinyl-modified phenolic resin.

[0007] As a further technical solution, the mass ratio of the boron-modified phenolic resin to the epoxy-modified phenolic resin is 3-5:1.

[0008] In the present invention, the specific surface area of ​​the phenolic resin-based porous carbon is further increased by adjusting the mass ratio of the boron-modified phenolic resin to the epoxy-modified phenolic resin to 3-5:1.

[0009] As a further technical solution, the mass ratio of the boron-modified phenolic resin to the epoxy-modified phenolic resin is 4:1.

[0010] In the present invention, the specific surface area of ​​the phenolic resin-based porous carbon is further increased by adjusting the mass ratio of the boron-modified phenolic resin to the epoxy-vinyl-modified phenolic resin to 4:1.

[0011] As a further technical solution, the curing agent includes hexamethylenetetramine; The binder comprises the following components in parts by weight: 20-34 parts of coal tar, 15-25 parts of starch, and 10-25 parts of water.

[0012] As a further technical solution, the starch includes one or more of corn starch, wheat starch, and sweet potato starch.

[0013] In the present invention, urotropine is used as a curing agent in the raw materials. When urotropine reacts with the phenolic resin, it can form a highly cross-linked three-dimensional network structure. It can fully react with the active groups in the phenolic resin, so that the resin molecular chains are tightly connected through chemical bonds, thereby increasing the cross-linking density of the cured resin and enhancing the mechanical properties and heat resistance of the material.

[0014] The binder used in the present invention has certain fluidity and viscosity. When added to the phenolic resin system, the fluidity of the phenolic resin in the processing process can be improved, making it easier to evenly mix with other additives and reinforcing materials, thereby improving the processing efficiency and the molding quality of the product.

[0015] The present invention also proposes a method for preparing the phenolic resin-based porous carbon, comprising the following steps: S1, mixing the phenolic resin and the curing agent, curing, and crushing to obtain phenolic resin powder; S2, grinding and mixing the phenolic resin powder and the remaining components of the phenolic resin-based porous carbon to obtain a mixture; S3, shaping the mixture, carbonizing it, and cooling it to room temperature to obtain phenolic resin-based porous carbon.

[0016] As a further technical solution, the carbonization is divided into three stages. In the first stage, the temperature is increased to 120-160°C at 3-8°C / min and kept warm for 1-2 hours. In the second stage, the temperature is increased to 450-520°C at 14-17°C / min and kept warm for 0.5-1.5 hours. In the third stage, the temperature is increased to 900-950°C at 9-13°C / min and kept warm for 3-6 hours.

[0017] In the present invention, a specific carbonization method is used to improve the yield of phenolic resin-based porous carbon.

[0018] As a further technical solution, the carbonization atmosphere is an inert gas.

[0019] As a further technical solution, the inert gas includes one of nitrogen and argon.

[0020] As a further technical solution, the particle size of the solid particles in the mixture is 5-15 μm.

[0021] The working principle and beneficial effects of the present invention are: In the present invention, the introduction of boron element in the boron-modified phenolic resin can make the molecular structure of the phenolic resin more stable, and can better maintain the skeleton structure of the resin during the carbonization process, reducing the collapse and destruction of the structure. This is conducive to forming more and more regular pore structures and improving its adsorption activity. The introduction of epoxy vinyl in the epoxy vinyl-modified phenolic resin gives the phenolic resin better flexibility and reactivity, and after being compounded with the boron-modified phenolic resin, the processing performance and molding performance of the resin are improved, the pore structure of the porous carbon is further optimized, and the specific surface area of ​​the porous carbon is improved. DETAILED DESCRIPTION

[0022] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In the following examples and comparative examples, boron-modified phenolic resin was purchased from Jining Tangyi Chemical Co., Ltd.; epoxy vinyl-modified phenolic resin, also known as phenolic epoxy vinyl resin, model 907; coal tar was purchased from Hebei Deri New Materials Technology Co., Ltd.; and the corn starch particle size was 15-25 μm.

[0024] Example 1 A phenolic resin-based porous carbon, the raw materials include the following components in parts by weight: 100 parts of phenolic resin, 10 parts of curing agent, 18 parts of binder, and 21 parts of urea; The phenolic resin includes a boron-modified phenolic resin and an epoxy-vinyl-modified phenolic resin in a mass ratio of 8:1; Curing agents include hexamethylenetetramine; The binder includes the following components in parts by weight: 34 parts of coal tar, 25 parts of corn starch, and 25 parts of water; The preparation method of phenolic resin-based porous carbon comprises the following steps: S1, mixing phenolic resin and curing agent, curing, and crushing to obtain phenolic resin powder; S2, grinding the phenolic resin powder and the remaining components of the phenolic resin-based porous carbon to a particle size of 15 μm, mixing, and obtaining a mixture; S3, molding the mixture, carbonizing it, and cooling it to room temperature to obtain phenolic resin-based porous carbon; The carbonization was divided into three stages: in the first stage, the temperature was raised to 140°C at 2°C / min and kept at this temperature for 1.5 h; in the second stage, the temperature was raised to 470°C at 13°C / min and kept at this temperature for 1 h; in the third stage, the temperature was raised to 930°C at 8°C / min and kept at this temperature for 4 h; The carbonization atmosphere was nitrogen.

[0025] Example 2 A phenolic resin-based porous carbon, the raw materials include the following components in parts by weight: 85 parts of phenolic resin, 5 parts of curing agent, 10 parts of binder, and 17 parts of urea; The phenolic resin includes a boron-modified phenolic resin and an epoxy-vinyl-modified phenolic resin in a mass ratio of 1:1; Curing agents include hexamethylenetetramine; The binder includes the following components in parts by weight: 20 parts of coal tar, 15 parts of wheat starch, and 10 parts of water; The preparation method of phenolic resin-based porous carbon comprises the following steps: S1, mixing phenolic resin and curing agent, curing, and crushing to obtain phenolic resin powder; S2, grinding the phenolic resin powder and the remaining components of the phenolic resin-based porous carbon to a particle size of 5 μm, mixing, and obtaining a mixture; S3, molding the mixture, carbonizing it, and cooling it to room temperature to obtain phenolic resin-based porous carbon; The carbonization was divided into three stages: in the first stage, the temperature was raised to 140°C at 2°C / min and kept at this temperature for 1.5 h; in the second stage, the temperature was raised to 470°C at 13°C / min and kept at this temperature for 1 h; in the third stage, the temperature was raised to 930°C at 8°C / min and kept at this temperature for 4 h; The carbonization atmosphere was argon.

[0026] Example 3 A phenolic resin-based porous carbon, the raw materials include the following components in parts by weight: 90 parts of phenolic resin, 8 parts of curing agent, 14 parts of binder, and 18 parts of urea; The phenolic resin includes a boron-modified phenolic resin and an epoxy-vinyl-modified phenolic resin in a mass ratio of 6:1; Curing agents include hexamethylenetetramine; The binder includes the following components in parts by weight: 26 parts of coal tar, 20 parts of sweet potato starch, and 19 parts of water; The preparation method of phenolic resin-based porous carbon comprises the following steps: S1, mixing phenolic resin and curing agent, curing, and crushing to obtain phenolic resin powder; S2, grinding the phenolic resin powder and the remaining components of the phenolic resin-based porous carbon to a particle size of 10 μm, mixing, and obtaining a mixture; S3, molding the mixture, carbonizing it, and cooling it to room temperature to obtain phenolic resin-based porous carbon; The carbonization was divided into three stages: in the first stage, the temperature was raised to 140°C at 2°C / min and kept at this temperature for 1.5 h; in the second stage, the temperature was raised to 470°C at 13°C / min and kept at this temperature for 1 h; in the third stage, the temperature was raised to 930°C at 8°C / min and kept at this temperature for 4 h; The carbonization atmosphere was nitrogen.

[0027] Example 4 The only difference between this embodiment and embodiment 3 is that the phenolic resin in this embodiment includes boron-modified phenolic resin and epoxy vinyl-modified phenolic resin in a mass ratio of 2:1.

[0028] Example 5 The only difference between this embodiment and embodiment 3 is that the phenolic resin in this embodiment includes boron-modified phenolic resin and epoxy vinyl-modified phenolic resin in a mass ratio of 3:1.

[0029] Example 6 The only difference between this embodiment and embodiment 3 is that the phenolic resin in this embodiment includes boron-modified phenolic resin and epoxy vinyl-modified phenolic resin in a mass ratio of 4:1.

[0030] Example 7 The only difference between this embodiment and embodiment 3 is that the phenolic resin in this embodiment includes boron-modified phenolic resin and epoxy vinyl-modified phenolic resin in a mass ratio of 5:1.

[0031] Example 8 The only difference between this embodiment and embodiment 3 is that the carbonization in this embodiment is divided into three stages. In the first stage, the temperature is increased to 140°C at 9°C / min and kept warm for 1.5 hours. In the second stage, the temperature is increased to 470°C at 13°C / min and kept warm for 1 hour. In the third stage, the temperature is increased to 930°C at 8°C / min and kept warm for 4 hours.

[0032] Example 9 The only difference between this embodiment and embodiment 3 is that the carbonization in this embodiment is divided into three stages. In the first stage, the temperature is increased to 140°C at 3°C / min and kept warm for 1.5 hours. In the second stage, the temperature is increased to 470°C at 13°C / min and kept warm for 1 hour. In the third stage, the temperature is increased to 930°C at 8°C / min and kept warm for 4 hours.

[0033] Example 10 The only difference between this embodiment and embodiment 3 is that the carbonization in this embodiment is divided into three stages. In the first stage, the temperature is increased to 140°C at 2°C / min and kept warm for 1.5 hours. In the second stage, the temperature is increased to 470°C at 18°C / min and kept warm for 1 hour. In the third stage, the temperature is increased to 930°C at 8°C / min and kept warm for 4 hours.

[0034] Embodiment 11 The only difference between this embodiment and embodiment 3 is that the carbonization in this embodiment is divided into three stages. In the first stage, the temperature is increased to 140°C at 2°C / min and kept warm for 1.5 hours. In the second stage, the temperature is increased to 470°C at 14°C / min and kept warm for 1 hour. In the third stage, the temperature is increased to 930°C at 8°C / min and kept warm for 4 hours.

[0035] Example 12 The only difference between this embodiment and embodiment 3 is that the carbonization in this embodiment is divided into three stages. In the first stage, the temperature is increased to 140°C at 2°C / min and kept warm for 1.5 hours. In the second stage, the temperature is increased to 470°C at 13°C / min and kept warm for 1 hour. In the third stage, the temperature is increased to 930°C at 14°C / min and kept warm for 4 hours.

[0036] Embodiment 13 The only difference between this embodiment and embodiment 3 is that the carbonization in this embodiment is divided into three stages. In the first stage, the temperature is increased to 140°C at 2°C / min and kept warm for 1.5 hours. In the second stage, the temperature is increased to 470°C at 13°C / min and kept warm for 1 hour. In the third stage, the temperature is increased to 930°C at 9°C / min and kept warm for 4 hours.

[0037] Embodiment 14 The only difference between this embodiment and embodiment 3 is that the carbonization in this embodiment is divided into three stages. In the first stage, the temperature is increased to 120°C at 3°C / min and kept warm for 2 hours. In the second stage, the temperature is increased to 450°C at 14°C / min and kept warm for 1.5 hours. In the third stage, the temperature is increased to 900°C at 9°C / min and kept warm for 3 hours.

[0038] Embodiment 15 The only difference between this embodiment and embodiment 3 is that the carbonization in this embodiment is divided into three stages. In the first stage, the temperature is increased to 140°C at 5°C / min and kept warm for 1.5 hours. In the second stage, the temperature is increased to 470°C at 15°C / min and kept warm for 1 hour. In the third stage, the temperature is increased to 930°C at 11°C / min and kept warm for 4 hours.

[0039] Example 16 The only difference between this embodiment and embodiment 3 is that the carbonization in this embodiment is divided into three stages. In the first stage, the temperature is increased to 160°C at 8°C / min and kept warm for 1 hour. In the second stage, the temperature is increased to 520°C at 17°C / min and kept warm for 0.5 hour. In the third stage, the temperature is increased to 950°C at 13°C / min and kept warm for 3 hours.

[0040] Comparative Example 1 The only difference between this comparative example and Example 2 is that the raw materials of this comparative example include the following components in parts by weight: 85 parts of boron-modified phenolic resin, 5 parts of curing agent, 10 parts of binder, and 17 parts of urea.

[0041] Comparative Example 2 The only difference between this comparative example and Example 2 is that the raw materials of this comparative example include the following components in parts by weight: 85 parts of epoxy vinyl modified phenolic resin, 5 parts of curing agent, 10 parts of binder, and 17 parts of urea.

[0042] Experimental Example 1 The specific surface area of ​​the phenolic resin-based porous carbon prepared in Examples 1 to 7 and Comparative Examples 1 to 2 was tested by the following method: using a 3H 2000 BEST instrument, the nitrogen adsorption isotherm of the phenolic resin-based porous carbon was measured, and the specific surface area was calculated according to the BET formula. The test results are shown in Table 1.

[0043]

[0044] Comparing Example 2 with Comparative Examples 1-2, it is shown that the boron-modified phenolic resin and the epoxy-modified phenolic resin are simultaneously used as raw materials for the phenolic resin-based porous carbon in the present invention, thereby increasing the specific surface area of ​​the phenolic resin-based porous carbon.

[0045] Comparing Examples 5 to 7 with Examples 3 to 4, it is shown that when the mass ratio of the boron-modified phenolic resin to the epoxy-modified phenolic resin is 3 to 5:1, the specific surface area of ​​the phenolic resin-based porous carbon is further increased.

[0046] Experimental Example 2 The yield of the phenolic resin-based porous carbon obtained in Examples 3 and 8 to 16 was calculated using the following formula: A=m1 / m; A is the yield of phenolic resin-based porous carbon; m1 is the mass of phenolic resin-based porous carbon; m is the mass of raw materials; The test results are shown in Table 2.

[0047]

[0048] Comparing Example 9, Example 11, and Examples 13 to 16 with Example 3, Example 8, Example 10, and Example 12, it is shown that the present invention uses a specific carbonization method to improve the yield of phenolic resin-based porous carbon.

[0049] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A phenolic resin-based porous carbon, characterized in that: The raw materials include the following components in parts by weight: 85-100 parts of phenolic resin, 5-10 parts of curing agent, 10-18 parts of binder, and 17-21 parts of urea; The phenolic resin includes boron-modified phenolic resin and epoxy vinyl-modified phenolic resin.

2. A phenolic resin-based porous carbon according to claim 1, characterized in that: The mass ratio of the boron-modified phenolic resin to the epoxy-vinyl-modified phenolic resin is 3 to 5:

1.

3. A phenolic resin-based porous carbon according to claim 2, characterized in that: The mass ratio of the boron-modified phenolic resin to the epoxy-vinyl-modified phenolic resin is 4:

1.

4. The phenolic resin-based porous carbon according to claim 1, characterized in that: The curing agent includes hexamethylenetetramine; The binder comprises the following components in parts by weight: 20-34 parts of coal tar, 15-25 parts of starch, and 10-25 parts of water.

5. A phenolic resin-based porous carbon according to claim 4, characterized in that: The starch includes one or more of corn starch, wheat starch and sweet potato starch.

6. The method for preparing phenolic resin-based porous carbon according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1, mixing the phenolic resin and the curing agent, curing, and crushing to obtain phenolic resin powder; S2, grinding and mixing the phenolic resin powder and the remaining components of the phenolic resin-based porous carbon to obtain a mixture; S3, shaping the mixture, carbonizing it, and cooling it to room temperature to obtain phenolic resin-based porous carbon.

7. The method for preparing phenolic resin-based porous carbon according to claim 6, characterized in that: The carbonization is divided into three stages. In the first stage, the temperature is increased to 120-160°C at 3-8°C / min and kept warm for 1-2 hours. In the second stage, the temperature is increased to 450-520°C at 14-17°C / min and kept warm for 0.5-1.5 hours. In the third stage, the temperature is increased to 900-950°C at 9-13°C / min and kept warm for 3-6 hours.

8. The method for preparing phenolic resin-based porous carbon according to claim 6, characterized in that: The carbonization atmosphere is an inert gas.

9. The method for preparing phenolic resin-based porous carbon according to claim 8, characterized in that: The inert gas includes one of nitrogen and argon.

10. The method for preparing phenolic resin-based porous carbon according to claim 6, characterized in that: The particle size of the solid particles in the mixture is 5-15 μm.

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