CN118516852B - Chemical activation process for carbon fiber battery felt catalyst - Google Patents

Abstract

The present invention provides a carbon fiber battery felt catalyst chemical activation process, which relates to the technical field of activated carbon fiber preparation. The process comprises the following steps: impregnating a carbon fiber selected from polyacrylonitrile, asphalt fiber, phenolic fiber, viscose fiber, wood fiber, sisal fiber, ramie fiber, and cotton fiber in a catalyst, and drying the carbon fiber; after drying, slowly heating the carbon fiber, fully oxidizing it in the air, and then cooling it to room temperature; placing the oxidized carbon fiber in a tubular high-temperature furnace, heating it under the protection of nitrogen, activating it with water vapor, and then drying it. The combination of high specific surface area and yield of the carbon fiber battery felt prepared by the present invention enables the activated carbon fiber to have excellent performance in the field of energy storage and conversion.

Description

Chemical Activation Process of Carbon Fiber Battery Felt Catalyst

Technical Field

The invention relates to the technical field of active carbon fiber preparation, in particular to a process for chemical activation of carbon fiber battery felt catalyst.

Background Art

Activated carbon fiber is an ideal and efficient adsorption material, which is developed on the basis of the combination of carbon fiber technology and activated carbon technology. Activated carbon fiber is the third generation of activated carbon products after granular activated carbon and powdered activated carbon. Due to its special surface chemical structure and physical adsorption characteristics, it is widely used in environmental protection, medical hygiene, chemical industry and other fields.

The patent with authorization announcement number CN103290526B discloses a method for preparing wood activated carbon fibers by physical activation using wood biomass as raw materials. The method comprises placing wood powder in a liquefaction device, adding a polyol mixture as a liquefier, and preparing a liquefied product under acid catalysis conditions; adding a synthetic agent to synthesize a spinning solution, and then melt spinning to obtain fiber precursors; finally, placing the precursors in a carbonization and activation device, and using water vapor as an activator to prepare wood activated carbon fibers.

The patent application with publication number CN105220275A discloses a method for preparing activated carbon fibers using cellulose. Specifically, cellulose acetate is placed in a liquefaction reactor, phenol and an acid catalyst are added to obtain a cellulose phenol resin; a certain proportion of acetone is added to the resin as a solvent to synthesize a spinning solution, and the spinning solution is melt-spun and thermally cured under certain conditions to prepare cellulose precursors; the precursors are placed in a carbonization and activation device, and cellulose-based activated carbon fibers are prepared through a carbonization and activation process.

The patent application with publication number CN109735830A discloses an activation solution and a preparation method and a preparation method of a carbon fiber composite material. An activation solution is made of the following components: a dispersant, sodium citrate, a nickel salt and a boron-containing compound; the boron-containing compound is potassium borohydride or sodium borohydride; the pH value of the activation solution is 9 to 11. The dispersant in the activation solution can prevent the carbon fiber from agglomerating in an aqueous solution and can prevent the carbon fiber from agglomerating again after activation and washing. The activation solution is integrated, and the carbon fiber only needs to be placed in the activation solution to complete the steps of dispersing, sensitizing and activating the carbon fiber.

However, the existing production process has low yield and high cost; although the chemical activation method can greatly improve the product yield, it requires multiple water washings, and the product is brittle and difficult to be promoted in production.

Summary of the invention

The purpose of the present invention is to provide a process for chemical activation of carbon fiber battery felt catalyst. The combination of high specific surface area and yield of the carbon fiber battery felt prepared by this method makes the activated carbon fiber have excellent performance in the field of energy storage and conversion.

The technical solution adopted by the present invention is:

The carbon fiber battery felt catalyst chemical activation process includes the following steps:

S1: impregnating a carbon fiber selected from the group consisting of polyacrylonitrile, asphalt fiber, phenolic fiber, viscose fiber, wood fiber, sisal fiber, ramie fiber, and cotton fiber in a catalyst and drying the carbon fiber;

S2: After drying, the carbon fiber is slowly heated to 240-250°C, fully oxidized in the air, and then cooled to room temperature;

S3: placing the oxidized carbon fiber in a tubular high-temperature furnace, heating it under the protection of nitrogen, activating it with water vapor, and then drying it;

The preparation method of the catalyst comprises the following steps:

0.03-0.6 parts of 12-mercaptododecyl cerium phosphate complex and 0.05-0.5 parts of 1-allylpyrrolidine-2-carboxylic acid nickel complex are added into a reaction kettle, and then 2-6 parts of sodium ethoxide and 200-300 parts of acetone are added, and the mixture is stirred evenly and heated to 45-55° C. and reacted for 100-150 minutes; then 10-20 parts of ammonium phosphate and 1-6 parts of (S)-1,2-epoxy-5-hexene are added, and the mixture is kept warm and mixed for 100-150 minutes to obtain the desired catalyst.

Furthermore, the preparation method of the 12-mercaptododecyl cerium phosphate complex is:

10-17 parts of 12-mercaptododecyl phosphoric acid and 3-6 parts of cerium nitrate are weighed into a reaction kettle, added into 100-200 parts of water, reacted at 30-40° C. for 30-90 minutes, and then the water is removed by distillation to obtain a cerium 12-mercaptododecyl phosphoric acid complex.

Furthermore, the preparation method of the 1-allylpyrrolidine-2-carboxylic acid nickel complex is:

12-20 parts of 1-allylpyrrolidine-2-carboxylic acid and 2-5 parts of nickel nitrate are weighed into a reaction kettle, added into 200-300 parts of water, reacted at 40-60° C. for 20-40 minutes, and then the water is removed by distillation to obtain 1-allylpyrrolidine-2-carboxylic acid nickel complex.

Furthermore, the immersion time of S1 is 30-60 minutes.

Furthermore, the oxidation time of S2 is 60-90 min.

Furthermore, the heating rate of S2 is 3-5°C/min.

Furthermore, during the water vapor activation process of S3, the carbon fiber is maintained at a temperature of 800-900° C. for 1-3 hours to ensure that the surface of the carbon fiber is fully activated, thereby improving its electrochemical performance in the battery.

Reaction mechanism: thiol-ene addition reaction:

The thiol group (-SH) in the cerium 12-mercaptododecylphosphate complex undergoes an addition reaction with the alkenyl group (C=C) in the nickel 1-allylpyrrolidine-2-carboxylate complex; the reaction may proceed via a Michael addition mechanism, in which the thiol group acts as a nucleophile to attack the β-carbon atom of the alkenyl group to form a carbon-sulfur bond.

Thiol-epoxy addition reaction:

The remaining thiol group in the addition product undergoes a ring-opening addition reaction with the epoxy group in (S)-1,2-epoxy-5-hexene, and the thiol group attacks the less substituted carbon atom in the epoxy group, resulting in the opening of the epoxy ring and the formation of a new carbon-sulfur bond.

Compounding:

The addition product is complexed with ammonium phosphate, involving hydrogen bond formation or other non-covalent interactions, to produce the final catalyst structure; this complexation can improve the thermal stability, mechanical strength or catalytic activity of the catalyst.

Beneficial effects: 1. Modification of carbon fiber felt: Using the catalyst of the present invention to modify the carbon fiber felt can significantly improve its porosity and average pore size; this modification enables the carbon fiber felt to have better electrolyte permeability and ion transfer efficiency in battery applications.

2. Activated carbon fiber performance: The activated carbon fiber prepared by the present invention has the following characteristics:

The specific surface area is as high as ^2155m2 /g, which provides a large surface active area for electrochemical reactions and enhances the charge storage and transfer capabilities;

The yield reached 59.37%, which indicates that the effective utilization rate of raw materials was high during the activation process, reducing material waste;

Comprehensive performance: The combination of high specific surface area and yield makes activated carbon fiber have excellent performance in the field of energy storage and conversion.

DETAILED DESCRIPTION

In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a detailed description in combination with embodiments and comparative examples:

Specific surface area determination: refer to GB2596-81 nitrogen adsorption method and use JB-1 specific surface area measuring instrument for determination.

Example 1: A process for chemical activation of a carbon fiber battery felt catalyst, comprising the following steps:

S1: impregnating carbon fiber selected from polyacrylonitrile in a catalyst and drying the carbon fiber;

S2: After drying, the carbon fiber is slowly heated to 240°C, fully oxidized in air, and then cooled to room temperature;

S3: placing the oxidized carbon fiber in a tubular high-temperature furnace, heating it under the protection of nitrogen, activating it with water vapor, and then drying it.

The preparation method of the catalyst comprises the following steps:

0.03 g of 12-mercaptododecyl cerium phosphate complex and 0.05 g of 1-allylpyrrolidine-2-carboxylic acid nickel complex were added to a reaction kettle, and then 2 g of sodium ethoxide and 200 g of acetone were added, and the mixture was stirred evenly and heated to 45° C. to react for 100 minutes; then 10 g of ammonium phosphate and 1 g of (S)-1,2-epoxy-5-hexene were added, and the mixture was kept warm and mixed for 100 minutes to obtain the desired catalyst.

The preparation method of the 12-mercaptododecyl cerium phosphate complex is as follows:

10 g of 12-mercaptododecyl phosphoric acid and 3 g of cerium nitrate were weighed into a reaction kettle, added into 100 g of water, reacted at 30° C. for 30 minutes, and then the water was removed by distillation to obtain a cerium 12-mercaptododecyl phosphoric acid complex.

The preparation method of the 1-allylpyrrolidine-2-carboxylic acid nickel complex is as follows:

12 g of 1-allylpyrrolidine-2-carboxylic acid and 2 g of nickel nitrate were weighed into a reaction kettle, added into 200 g of water, reacted at 40° C. for 20 minutes, and then the water was removed by distillation to obtain 1-allylpyrrolidine-2-carboxylic acid nickel complex.

The immersion time of S1 is 30 minutes.

The oxidation time of S2 is 60 min.

The heating rate of S2 is 3°C/min.

During the water vapor activation process of S3, the carbon fiber is kept at a temperature of 800° C. for 1 hour to ensure that the surface of the carbon fiber is fully activated, thereby improving its electrochemical performance in the battery.

Example 2: A process for chemically activating a carbon fiber battery felt catalyst, comprising the following steps:

S1: impregnating carbon fiber selected from pitch fiber in a catalyst and drying the catalyst;

S2: After drying, the carbon fiber is slowly heated to 245°C, fully oxidized in air, and then cooled to room temperature;

S3: placing the oxidized carbon fiber in a tubular high-temperature furnace, heating it under the protection of nitrogen, activating it with water vapor, and then drying it.

The preparation method of the catalyst comprises the following steps:

0.2 g of 12-mercaptododecyl cerium phosphate complex and 0.2 g of 1-allylpyrrolidine-2-carboxylic acid nickel complex were added to a reaction kettle, and then 3 g of sodium ethoxide and 240 g of acetone were added. After stirring evenly, the temperature was raised to 48° C. and the reaction was carried out for 110 minutes. Subsequently, 13 g of ammonium phosphate and 2 g of (S)-1,2-epoxy-5-hexene were added, and the mixture was kept warm and mixed for 110 minutes to obtain the desired catalyst.

The preparation method of the 12-mercaptododecyl cerium phosphate complex is as follows:

12 g of 12-mercaptododecyl phosphoric acid and 4 g of cerium nitrate were weighed into a reaction kettle, added into 140 g of water, reacted at 35° C. for 50 minutes, and then the water was removed by distillation to obtain a cerium 12-mercaptododecyl phosphoric acid complex.

The preparation method of the 1-allylpyrrolidine-2-carboxylic acid nickel complex is as follows:

14 g of 1-allylpyrrolidine-2-carboxylic acid and 3 g of nickel nitrate were weighed into a reaction kettle, added to 240 g of water, reacted at 45° C. for 25 minutes, and then the water was removed by distillation to obtain 1-allylpyrrolidine-2-carboxylic acid nickel complex.

The immersion time of S1 is 40 minutes.

The oxidation time of S2 is 70 min.

The heating rate of S2 is 4°C/min.

During the water vapor activation process of S3, the carbon fiber is kept at a temperature of 840° C. for 2 hours to ensure that the surface of the carbon fiber is fully activated, thereby improving its electrochemical performance in the battery.

Example 3: A process for chemical activation of a carbon fiber battery felt catalyst, comprising the following steps:

S1: impregnating carbon fiber selected from phenolic fiber in a catalyst and drying it;

S2: After drying, the carbon fiber is slowly heated to 245°C, fully oxidized in air, and then cooled to room temperature;

S3: placing the oxidized carbon fiber in a tubular high-temperature furnace, heating it under the protection of nitrogen, activating it with water vapor, and then drying it.

The preparation method of the catalyst comprises the following steps:

0.5 g of 12-mercaptododecyl cerium phosphate complex and 0.4 g of 1-allylpyrrolidine-2-carboxylic acid nickel complex were added to a reaction kettle, and then 5 g of sodium ethoxide and 280 g of acetone were added. After stirring evenly, the temperature was raised to 53° C. and the reaction lasted for 140 minutes. Subsequently, 18 g of ammonium phosphate and 5 g of (S)-1,2-epoxy-5-hexene were added, and the mixture was kept warm and mixed for 40 minutes to obtain the desired catalyst.

The preparation method of the 12-mercaptododecyl cerium phosphate complex is as follows:

16 g of 12-mercaptododecyl phosphoric acid and 5 g of cerium nitrate were weighed into a reaction kettle, added into 180 g of water, reacted at 35° C. for 70 minutes, and then the water was removed by distillation to obtain a 12-mercaptododecyl phosphoric acid cerium complex.

The preparation method of the 1-allylpyrrolidine-2-carboxylic acid nickel complex is as follows:

18 g of 1-allylpyrrolidine-2-carboxylic acid and 4 g of nickel nitrate were weighed into a reaction kettle, added into 280 g of water, reacted at 55° C. for 35 minutes, and then the water was removed by distillation to obtain 1-allylpyrrolidine-2-carboxylic acid nickel complex.

The immersion time of S1 is 50 minutes.

The oxidation time of S2 is 80 min.

The heating rate of S2 is 4°C/min.

During the water vapor activation process of S3, the carbon fiber is kept at a temperature of 880° C. for 2 hours to ensure that the surface of the carbon fiber is fully activated, thereby improving its electrochemical performance in the battery.

Example 4: A process for chemically activating a carbon fiber battery felt catalyst, comprising the following steps:

S1: impregnating carbon fiber selected from cotton fiber in a catalyst and drying it;

S2: After drying, the carbon fiber is slowly heated to 250°C, fully oxidized in air, and then cooled to room temperature;

S3: placing the oxidized carbon fiber in a tubular high-temperature furnace, heating it under the protection of nitrogen, activating it with water vapor, and then drying it.

The preparation method of the catalyst comprises the following steps:

0.6 g of 12-mercaptododecyl cerium phosphate complex and 0.5 g of 1-allylpyrrolidine-2-carboxylic acid nickel complex were added to a reaction kettle, and then 6 g of sodium ethoxide and 300 g of acetone were added. After stirring evenly, the temperature was raised to 55° C. and the reaction was carried out for 150 minutes. Subsequently, 20 g of ammonium phosphate and 6 g of (S)-1,2-epoxy-5-hexene were added, and the mixture was mixed for 150 minutes under heat preservation to obtain the desired catalyst.

The preparation method of the 12-mercaptododecyl cerium phosphate complex is as follows:

17 g of 12-mercaptododecyl phosphoric acid and 6 g of cerium nitrate were weighed into a reaction kettle, added into 200 g of water, reacted at 40° C. for 90 minutes, and then the water was removed by distillation to obtain a 12-mercaptododecyl phosphoric acid cerium complex.

The preparation method of the 1-allylpyrrolidine-2-carboxylic acid nickel complex is as follows:

20 g of 1-allylpyrrolidine-2-carboxylic acid and 5 g of nickel nitrate were weighed into a reaction kettle, added into 300 g of water, reacted at 60° C. for 40 minutes, and then the water was removed by distillation to obtain 1-allylpyrrolidine-2-carboxylic acid nickel complex.

The immersion time of S1 is 60 minutes.

The oxidation time of S2 is 90 min.

The heating rate of S2 is 5°C/min.

During the water vapor activation process of S3, the carbon fiber is kept at a temperature of 900° C. for 3 hours to ensure that the surface of the carbon fiber is fully activated, thereby improving its electrochemical performance in the battery.

Comparative Example 1: No 12-mercaptododecyl cerium phosphate complex was added, and the other steps were the same as in Example 1.

Comparative Example 2: No 1-allylpyrrolidine-2-carboxylic acid nickel complex was added, and the other steps were the same as in Example 1.

Comparative Example 3: (S)-1,2-epoxy-5-hexene was not added, and the other steps were the same as those in Example 1.

Table 1: Test results of various embodiments and comparative examples

Through the data analysis of the above embodiments and comparative examples, the carbon fiber battery felt prepared by the present invention has a high specific surface area and yield, so that the activated carbon fiber has excellent performance in the field of energy storage and conversion.

The above embodiments are only illustrative of the present invention and do not have any limiting effect. Any non-substantial modifications made by those skilled in the art on the basis of the present invention should fall within the protection scope of the present invention.

Claims (7)

1. A carbon fiber battery felt catalyst chemical activation process, characterized in that it comprises the following steps: S1: impregnating a carbon fiber prepared from one selected from polyacrylonitrile, asphalt fiber, phenolic fiber, viscose fiber, wood fiber, sisal fiber, ramie fiber, and cotton fiber in a catalyst and drying the carbon fiber; S2: After drying, the carbon fiber is slowly heated to 240-250°C, fully oxidized in the air, and then cooled to room temperature; S3: placing the oxidized carbon fiber in a tubular high-temperature furnace, heating it under the protection of nitrogen, activating it with water vapor, and then drying it; The preparation method of the catalyst comprises the following steps: According to the mass proportion, 0.03-0.6 parts of 12-mercaptododecyl cerium phosphate complex and 0.05-0.5 parts of 1-allylpyrrolidine-2-carboxylic acid nickel complex are added into a reaction kettle, and then 2-6 parts of sodium ethoxide and 200-300 parts of acetone are added, and the mixture is stirred evenly and heated to 45-55° C. and reacted for 100-150 minutes; then 10-20 parts of ammonium phosphate and 1-6 parts of (S)-1,2-epoxy-5-hexene are added, and the mixture is mixed and kept warm for 100-150 minutes to obtain the desired catalyst. 2. The carbon fiber battery felt catalyst chemical activation process according to claim 1, characterized in that: the preparation method of the 12-mercaptododecyl cerium phosphate complex is: 10-17 parts of 12-mercaptododecyl phosphoric acid and 3-6 parts of cerium nitrate are weighed in a reaction kettle by mass, added into 100-200 parts of water, reacted at 30-40° C. for 30-90 minutes, and then the water is removed by distillation to obtain a cerium 12-mercaptododecyl phosphate complex. 3. The carbon fiber battery felt catalyst chemical activation process according to claim 1, characterized in that: the preparation method of the 1-allylpyrrolidine-2-carboxylic acid nickel complex is: 12-20 parts of 1-allylpyrrolidine-2-carboxylic acid and 2-5 parts of nickel nitrate are weighed in a reaction kettle by mass, added into 200-300 parts of water, reacted at 40-60° C. for 20-40 minutes, and then the water is removed by distillation to obtain a 1-allylpyrrolidine-2-carboxylic acid nickel complex. 4. The carbon fiber battery felt catalyst chemical activation process according to claim 1, characterized in that the impregnation time of S1 is 30-60 minutes. 5. The carbon fiber battery felt catalyst chemical activation process according to claim 1, characterized in that the oxidation time of S2 is 60-90 minutes. 6. The carbon fiber battery felt catalyst chemical activation process according to claim 1, characterized in that the heating rate of S2 is 3-5°C/min. 7. The process for chemical activation of carbon fiber battery felt catalyst according to claim 1, characterized in that during the water vapor activation process of S3, the carbon fiber is kept at a temperature of 800-900°C for 1-3h.