A low-cost simple preparing method for nitrogen-doped porous charcoal with a high specific surface area

Abstract

A low-cost simple preparing method for nitrogen-doped porous charcoal with a high specific surface area is disclosed. The method is characterized in that a characteristic that soybean meal absorbs water and then expands is utilized; a pretreating method in which soybean meal is soaked with a KOH solution is adopted to fully mix the KOH that is an activator and the soybean meal that is a precursor, thus achieving an objective of reducing the using amount of the activator; the specific surface area, the pore structure, the nitrogen content, and the like of the porous charcoal are adjusted and controlled through changing a plurality of process parameters, such as activation temperature (600-900 DEG C) and activation time (0.5-2 h); and the nitrogen-doped porous charcoal with the high specific surface area is prepared under a condition that the using amount of the activator is low.

Description

technical field

[0001] The invention relates to a low-cost and simple preparation method of nitrogen-doped porous carbon with high specific surface area, which is especially suitable for high specific capacitance and high specific power supercapacitors with a specific surface area of ​​600-2100m 2 / g of carbonaceous electrode materials. Background technique

[0002] Porous carbon materials are widely used in the fields of electric double layer supercapacitor electrode materials and adsorption materials due to their excellent stability, electrical conductivity, high specific surface area, and low cost. In electric double layer capacitors, the specific capacitance is mainly related to the pore structure, specific surface area and heteroatoms contained in the electrode material. The larger the effective adsorption specific surface area of ​​the electrode material, the more reasonable the pore structure is, which is the basis for the adsorption of electrons in the electric doubl...

Examples

Embodiment 1

[0015] a. Dry the commercially available soybean meal to remove its own moisture. Mix the dried soybean meal with KOH at a mass ratio of 4:1. KOH is prepared into a solution with a concentration of 50% before mixing, and soaked for 1 hour until the solution is fully absorbed by the soybean meal. can;

[0016] b. Place the mixture obtained in step a in a KOH activation kettle, raise the temperature to 100°C at a heating rate of 10°C / min under nitrogen protection, dehydrate at a constant temperature for 0.5h, then continue to heat up to the activation temperature to 600°C, keep it warm for 1h, and Cool directly to room temperature under room temperature environment;

[0017] c. Wash the substance obtained in step b with 5mol / L HCl and deionized water successively to remove the residual metal K and its compounds (that is, wash to neutrality), and dry it at 110°C to obtain activated carbon with a super high specific surface area .

[0018] The BET specific surface area of ​​the ...

Embodiment 2

[0020] a. Dry the commercially available soybean meal and soybean meal to remove its own moisture. Mix the dried soybean meal with KOH at a mass ratio of 4:1. KOH is prepared into a solution with a concentration of 50% before mixing, and soaked for 1 hour until the solution is fully covered by soybean meal. Just absorb;

[0021] b. Put the mixture obtained in step a in a KOH activation kettle, raise the temperature to 100°C at a heating rate of 10°C / min under nitrogen protection, dehydrate at a constant temperature for 0.5h, then continue to heat up to the activation temperature to 700°C, keep it warm for 1h, and Cool directly to room temperature under room temperature environment;

[0022] c. Wash the substance obtained in step b with 5mol / L HCl and deionized water successively to remove the residual metal K and its compounds (that is, wash to neutrality), and dry it at 110°C to obtain activated carbon with a super high specific surface area .

[0023] The BET specific surf...

Embodiment 3

[0025] a. Dry the commercially available soybean meal and soybean meal to remove its own moisture. Mix the dried soybean meal with KOH at a mass ratio of 4:1. KOH is prepared into a solution with a concentration of 50% before mixing, and soaked for 1 hour until the solution is fully covered by soybean meal. Just absorb;

[0026] b. Place the mixture obtained in step a in a KOH activation kettle, raise the temperature to 100°C at a heating rate of 10°C / min under nitrogen protection, dehydrate at a constant temperature for 0.5h, then continue to heat up to the activation temperature to 800°C, keep it warm for 1h, and Cool directly to room temperature under room temperature environment;

[0027] c. Wash the substance obtained in step b with 5mol / L HCl and deionized water successively to remove the residual metal K and its compounds (that is, wash to neutrality), and dry it at 110°C to obtain activated carbon with a super high specific surface area .

[0028] The BET specific su...

technical field

[0001] The invention relates to a low-cost and simple preparation method of nitrogen-doped porous carbon with high specific surface area, which is especially suitable for high specific capacitance and high specific power supercapacitors with a specific surface area of ​​600-2100m 2 / g of carbonaceous electrode materials. Background technique

[0002] Porous carbon materials are widely used in the fields of electric double layer supercapacitor electrode materials and adsorption materials due to their excellent stability, electrical conductivity, high specific surface area, and low cost. In electric double layer capacitors, the specific capacitance is mainly related to the pore structure, specific surface area and heteroatoms contained in the electrode material. The larger the effective adsorption specific surface area of ​​the electrode material, the more reasonable the pore structure is, which is the basis for the adsorption of electrons in the electric doubl...

Examples

Embodiment 1

[0015] a. Dry the commercially available soybean meal to remove its own moisture. Mix the dried soybean meal with KOH at a mass ratio of 4:1. KOH is prepared into a solution with a concentration of 50% before mixing, and soaked for 1 hour until the solution is fully absorbed by the soybean meal. can;

[0016] b. Place the mixture obtained in step a in a KOH activation kettle, raise the temperature to 100°C at a heating rate of 10°C / min under nitrogen protection, dehydrate at a constant temperature for 0.5h, then continue to heat up to the activation temperature to 600°C, keep it warm for 1h, and Cool directly to room temperature under room temperature environment;

[0017] c. Wash the substance obtained in step b with 5mol / L HCl and deionized water successively to remove the residual metal K and its compounds (that is, wash to neutrality), and dry it at 110°C to obtain activated carbon with a super high specific surface area .

[0018] The BET specific surface area of ​​the ...

Embodiment 2

[0020] a. Dry the commercially available soybean meal and soybean meal to remove its own moisture. Mix the dried soybean meal with KOH at a mass ratio of 4:1. KOH is prepared into a solution with a concentration of 50% before mixing, and soaked for 1 hour until the solution is fully covered by soybean meal. Just absorb;

[0021] b. Put the mixture obtained in step a in a KOH activation kettle, raise the temperature to 100°C at a heating rate of 10°C / min under nitrogen protection, dehydrate at a constant temperature for 0.5h, then continue to heat up to the activation temperature to 700°C, keep it warm for 1h, and Cool directly to room temperature under room temperature environment;

[0022] c. Wash the substance obtained in step b with 5mol / L HCl and deionized water successively to remove the residual metal K and its compounds (that is, wash to neutrality), and dry it at 110°C to obtain activated carbon with a super high specific surface area .

[0023] The BET specific surf...

Embodiment 3

[0025] a. Dry the commercially available soybean meal and soybean meal to remove its own moisture. Mix the dried soybean meal with KOH at a mass ratio of 4:1. KOH is prepared into a solution with a concentration of 50% before mixing, and soaked for 1 hour until the solution is fully covered by soybean meal. Just absorb;

[0026] b. Place the mixture obtained in step a in a KOH activation kettle, raise the temperature to 100°C at a heating rate of 10°C / min under nitrogen protection, dehydrate at a constant temperature for 0.5h, then continue to heat up to the activation temperature to 800°C, keep it warm for 1h, and Cool directly to room temperature under room temperature environment;

[0027] c. Wash the substance obtained in step b with 5mol / L HCl and deionized water successively to remove the residual metal K and its compounds (that is, wash to neutrality), and dry it at 110°C to obtain activated carbon with a super high specific surface area .

[0028] The BET specific su...