CN100467371C - Preparation method of porous carbon material - Google Patents

Abstract

A method for preparing a porous carbon material, using phenolic resin, ethylene glycol and benzenesulfonyl chloride as starting materials, and preparing nanoporous carbon with dual-stage pore size distribution of mesopores and macropores through processes such as initial curing molding, deep curing, and carbonization Plain block material. The control of porous carbon parameters such as pore morphology, pore size, and pore volume can be achieved by adjusting the starting material composition and deep curing temperature. The porous carbon has three kinds of pore shapes, the average pore diameter is less than 500nm, and the pore volume is 0.20-0.85cm ³ /g. The method uses the finished phenolic resin as the carbonaceous raw material, requires less equipment to complete initial curing molding, deep curing, and carbonization, and has the characteristics of low cost, easy industrial production, and the like. Due to the controllability of porous carbon pore properties, it is possible to prepare bulk porous carbon suitable for environmental protection, energy efficiency improvement and other applications, as well as prefabricated bodies prepared as carbide ceramics.

Description

Preparation method of porous carbon material

technical field

The invention relates to a method for preparing a carbon material, in particular to a method for preparing a porous carbon block material.

Background technique

Porous carbon materials have been paid close attention to because of their wide application value in gas separation, water purification, catalysis, chromatographic analysis, energy storage, and preparation of complex shapes and difficult-to-process engineering ceramics. These uses are closely related to the structure of porous carbon.

Activated carbon is the earliest porous carbon material used industrially. Micropores (pore diameter <2nm) account for a large proportion of activated carbon materials, which limits its application in macromolecular (or ion) systems. For example, in the application of adsorbing polymers, dyes, vitamins and other macromolecules. In contrast, mesoporous carbon with larger pore size (2nm<pore size<50nm) has a very prominent advantage in the adsorption of macromolecules. If the porous carbon material has mesopores and macropores at the same time, its application effect will be greatly improved, because the macropores provide a fast channel for macromolecules to enter the mesopores.

Using porous carbon as a prefabricated body can prepare complex shapes and difficult-to-process engineering ceramics to make up for the uncontrollable weakness of the pore structure of wood ceramics. Porous Carbon In this application, the structure of the pores has a great influence on the performance of the final ceramic part.

Therefore, how to effectively control the pore structure of porous carbon is of great significance.

At present, the main methods of preparing porous carbon include: catalytic activation method, organic polymer phase separation carbonization method, organogel carbonization method and template method. Among them, the organic polymer phase separation carbonization method can effectively control the pore structure of porous carbon. US Patent (3859421, 1975) used this method to prepare porous carbon with furfuryl alcohol resin or monomers of synthetic furfuryl alcohol resin as carbonaceous raw materials. Yan Xiang

Wang (Carbon 2003; 41:2065-2072) systematically studied the influence of process parameters on the porous carbon of furfuryl alcohol resin, and realized the control of the porous carbon pore structure.

Contents of the invention

Aiming at the characteristic that the application of porous carbon is affected by the pore structure, the present invention provides a method for preparing a porous carbon material in which thermosetting phenolic resin is used as a carbonaceous raw material to realize controllable pore structure.

In order to achieve the above object, the technical scheme adopted in the present invention is:

1) Mixing: First, mix and stir 2130# thermosetting phenolic resin and ethylene glycol at a weight ratio of 1:1 to 1:4, then add benzenesulfonyl chloride with 4 to 15% of the total weight of phenolic resin and ethylene glycol and mix make a homogeneous mixture;

2) Initial curing molding: pour the mixture into the mold and keep it warm at 50°C for 3h to 6h;

3) Deep curing: Demould the sample after initial curing, carry out deep curing treatment on the sample, keep it at the initial temperature of 60°C for 8-16h, and then keep it for 8-16h for every 20°C increase in temperature until the temperature rises to 100°C ~180℃ and then keep warm for 8~16h;

4) Carbonization: Carry out carbonization under the protection of N ₂ , rise from room temperature to 600°C, hold for 1 hour, and the heating rate is 1.5°C/min. After carbonization is completed, cool down to room temperature with the furnace, and finally stop supplying N ₂ .

Due to the wide range of phenolic resin raw materials used in the present invention, the pore structure of the prepared porous carbon is controllable and the pore structure control means are diversified. The results prove that the average pore diameter of the porous carbon is less than 500nm; it has a dual-stage pore size distribution of mesopores and macropores; the pore volume can be varied between 0.20-0.67cm ³ /g by adjusting different contents of ethylene glycol. Adjusting different contents of benzenesulfonyl chloride can realize the change of pore volume between 0.33-0.85cm ³ /g. The pore volume can be changed between 0.43-0.70cm ³ /g by adjusting different deep curing temperatures. Three kinds of porous carbons with different pore shapes were obtained at the same time.

Description of drawings

Fig. 1 is the pore topography figure of the porous carbon of embodiment 1 of the present invention;

Fig. 2 is the pore topography figure of the porous carbon of embodiment 2 of the present invention;

Fig. 3 is the pore topography figure of the porous carbon of embodiment 3 of the present invention;

Fig. 4 is the pore topography figure of the porous carbon of embodiment 4 of the present invention;

Fig. 5 is a mesopore distribution diagram of the porous carbon of Example 2 of the present invention, wherein the abscissa is the pore diameter in nanometers, and the ordinate is the differential pore volume.

Detailed ways

The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments.

Example 1: First, mix and stir 2130# thermosetting phenolic resin and ethylene glycol in a weight ratio of 1:1, then add phenolic resin and benzenesulfonyl chloride with a total weight of 6% of ethylene glycol and mix evenly to make a mixture; curing and molding : Pour the mixture into the mold, heat it at 50°C for 4 hours and 15 minutes for initial curing and molding; demould the sample after initial curing, carry out deep curing treatment on the sample, and heat it at the initial temperature of 60°C for 16 hours , and then heated to 80°C for 8h, 100°C for 16h, 120°C for 8h, 140°C for 16h, 160°C for 8h, 180°C for 16h for deep curing; carbonization was carried out under the protection of N ₂ , from room temperature to 600 ℃, keep warm for 1h, and the heating rate is 1.5°C/min. After completing the carbonization, cool to room temperature with the furnace, and finally stop supplying N ₂ to make porous carbon. See Figure 1, the pore volume of the porous carbon obtained according to the preparation method of this example It was 0.41 cm ³ /g.

Example 2: First, mix and stir 2130# thermosetting phenolic resin and ethylene glycol in a weight ratio of 1:2.3, then add phenolic resin and benzenesulfonyl chloride with a total weight of 6% of ethylene glycol and mix evenly to make a mixture; curing and molding : Pour the mixture into the mold, heat it at 50°C for 5 hours and 20 minutes for initial curing and molding; demould the sample after initial curing, carry out deep curing treatment on the sample, and heat it at the initial temperature of 60°C for 16 hours , and then heated to 80°C for 8h, 100°C for 16h, 120°C for 8h, 140°C for 16h, 160°C for 8h, 180°C for 16h for deep curing; carbonization was carried out under the protection of N ₂ , from room temperature to 600 ℃, keep warm for 1h, and the heating rate is 1.5°C/min. After completing the carbonization, cool down to room temperature with the furnace, and finally stop supplying N ₂ to make porous carbon. See Figures 2 and 5. The pore volume is 0.67 cm ³ /g.

Example 3: First, mix and stir 2130# thermosetting phenolic resin and ethylene glycol at a weight ratio of 1:2.3, then add phenolic resin and benzenesulfonyl chloride with a total weight of 6% of ethylene glycol and mix evenly to make a mixture; curing and molding : Pour the mixture into the mold, heat it at 50°C for 5 hours and 20 minutes for initial curing and molding; demould the sample after initial curing, carry out deep curing treatment on the sample, and heat it at the initial temperature of 60°C for 16 hours , then raise the temperature to 80°C for 8 hours, and 100°C for 16 hours; carry out carbonization under the protection of _N2 , from room temperature to 600°C, hold for 1 hour, and the heating rate is 1.5°C/min. After carbonization, cool to room temperature with the furnace. Finally stop supplying N ₂ to produce porous carbon, see FIG. 3 , the pore volume of the porous carbon obtained according to the preparation method of this example is 0.70 cm ³ /g.

Example 4: First, mix and stir 2130# thermosetting phenolic resin and ethylene glycol in a weight ratio of 1:1, then add phenolic resin and benzenesulfonyl chloride with 15% of the total weight of ethylene glycol and mix evenly to make a mixture; curing and molding : pour the mixture into the mold, heat it at 50°C for 3 hours for initial curing; demould the sample after initial curing, carry out deep curing treatment on the sample, heat it at the initial temperature of 60°C for 16 hours, and then Heat up to 80°C for 8 hours, 100°C for 16h, 120°C for 8h, 140°C for 16h, 160°C for 8h, 180°C for 16h for deep curing; carbonize under the protection of _N2 , from room temperature to 600°C, Keep warm for 1 hour, the heating rate is 1.5°C/min, after the completion of carbonization, cool to room temperature with the furnace, and finally stop supplying N ₂ to make porous carbon, see Figure 4, the pore volume of the porous carbon obtained according to the preparation method of this example is 0.85 cm ³ /g.

Example 5: First, mix and stir 2130# thermosetting phenolic resin and ethylene glycol in a weight ratio of 1:4, then add phenolic resin and benzenesulfonyl chloride with 4% of the total weight of ethylene glycol and mix evenly to make a mixture; curing and molding : pour the mixture into the mold, heat it at 50°C for 6 hours for initial curing; demould the sample after initial curing, carry out deep curing treatment on the sample, heat it at the initial temperature of 60°C for 16 hours, and then Heat up to 80°C for 8h, 100°C for 16h, 120°C for 8h, 140°C for 16h for deep curing; carbonization is carried out under the protection _{of N2} , from room temperature to 600°C, hold for 1h, and the heating rate is 1.5°C/min , after the carbonization is completed, the furnace is cooled to room temperature, and the supply of N ₂ is finally stopped to make porous carbon.

Example 6: First, mix and stir 2130# thermosetting phenolic resin and ethylene glycol in a weight ratio of 1:2, then add phenolic resin and benzenesulfonyl chloride with 10% of the total weight of ethylene glycol and mix evenly to make a mixture; curing and molding : pour the mixture into the mold, heat it at 50°C for 3 hours for initial curing; demould the sample after initial curing, carry out deep curing treatment on the sample, heat it at the initial temperature of 60°C for 16 hours, and then Heat up to 80°C for 8 hours, 100°C for 16 hours, 120°C for 8 hours, 140°C for 16 hours, 160°C for 8 hours for deep curing; carbonize under the protection of _N2 , from room temperature to 600°C, hold for 1 hour, the heating rate 1.5°C/min. After carbonization, cool down to room temperature with the furnace, and finally stop supplying N ₂ to make porous carbon.

Example 7: First, mix and stir 2130# thermosetting phenolic resin and ethylene glycol in a weight ratio of 1:1.5, then add phenolic resin and benzenesulfonyl chloride with 12% of the total weight of ethylene glycol and mix evenly to make a mixture; curing and molding : Pour the mixture into the mold, heat it at 50°C for 5 hours for initial curing; demould the sample after initial curing, carry out deep curing treatment on the sample, heat it at the initial temperature of 60°C for 16 hours, and then Heat up to 80°C for 8 hours, 100°C for 16 hours, and 120°C for 8 hours for deep curing; carry out carbonization under the protection of _N2 , from room temperature to 600°C, hold for 1 hour, and the heating rate is 1.5°C/min. The furnace was cooled to room temperature, and finally the _nitrogen supply was stopped to produce porous carbon.

Claims (1)

1. A method for preparing a porous carbon material, characterized in that: 1) Mixing: First, mix and stir 2130# thermosetting phenolic resin and ethylene glycol at a weight ratio of 1:1 to 1:4, then add benzenesulfonyl chloride with 4 to 15% of the total weight of phenolic resin and ethylene glycol and mix make a homogeneous mixture; 2) Initial curing molding: pour the mixture into the mold and keep it warm at 50°C for 3h to 6h; 3) Deep curing: Demould the sample after initial curing, carry out deep curing treatment on the sample, keep it at the initial temperature of 60°C for 8-16h, and then keep it for 8-16h for every 20°C increase in temperature until the temperature rises to 100°C ~180℃ and then keep warm for 8~16h; 4) Carbonization: Carry out carbonization under the protection of N ₂ , rise from room temperature to 600°C, hold for 1 hour, and the heating rate is 1.5°C/min. After carbonization is completed, cool down to room temperature with the furnace, and finally stop supplying N ₂ .

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