Method for preparing porous conductive carbon with rice husks as raw materials

Abstract

The invention belongs to the high-valued application field of agricultural solid residues, and particularly relates to a method for preparing porous conductive carbon on the basis of rice husks. The method uses the rice husks as raw materials, conductive carbon is prepared through the catalytic, hole forming and other characteristics of products generated after heating decomposition of zinc carbonate, and the prepared materials has the advantages of being porous, highly dispersed, good in electrical conductivity and the like. According to the technical scheme, the rice husks are smashed first, and desilicication rice husk powder is prepared after hydrofluoric acid desilicication is carried out; zinc carbonate is then added to the desilicication rice husk powder, and the porous conductive carbon is obtained through high-temperature calcination.

Description

technical field

[0001] The invention belongs to the high-value application field of agricultural solid waste resources, and in particular relates to a preparation method of a rice husk-based porous conductive carbon material. Background technique

[0002] Agricultural solid waste is a kind of natural material with abundant resources on the earth. Straw is a common type of agricultural solid waste. Chinese patent CN 102107864 B discloses a method for preparing biomass conductive carbon. The method uses biomass such as straw as raw materials, and under the action of a catalyst, adopts high-temperature carbonization to prepare a conductive carbon material. However, the conductive carbon material prepared by this method has a narrow pore size distribution, and its application range is limited.

[0003] Rice husk is a common solid waste and a valuable natural resource containing silicon. According to statistics, the annual output of rice husk in my country has reached more th...

Examples

Embodiment 1

[0014] 1. Dry 1 kg of rice husk and pulverize it into 60-mesh rice husk powder, then add 8 kg of solute mass percentage concentration to 10% hydrofluoric acid solution, stir evenly, place in a hydrothermal reaction kettle, React at a constant temperature of 180°C for 5 hours; filter and wash until the filtrate is neutral, and dry to obtain desiliconized rice husk powder;

[0015] 2. Take 0.25 kg of desiliconized rice husk powder and 0.2 kg of zinc carbonate obtained in step 1, mix them evenly, place the resulting mixture in a tube furnace, and put it in a mixed atmosphere of nitrogen and argon (volume ratio: 1:1) Then, the temperature was raised to 800°C at a rate of 15°C / min, kept at this temperature for 3 hours, and then cooled to room temperature (25°C) to prepare a porous conductive carbon composite material.

Embodiment 2

[0017] 1. Dry 0.5 kg of rice husk and pulverize it into 60-mesh rice husk powder, then add 10 kg of solute mass percentage concentration to 5% hydrofluoric acid solution, stir evenly, place in a hydrothermal reaction kettle, React at a constant temperature of 160°C for 2 hours; filter and wash until the filtrate is neutral, and dry to obtain desiliconized rice husk powder;

[0018] 2. Take 0.1 kg of desiliconized rice husk powder and 0.2 kg of zinc carbonate obtained in step 1, mix them evenly, place the resulting mixture in a tube furnace, and raise the temperature at a rate of 10°C / min under a nitrogen atmosphere. to 600°C, and kept at this temperature for 1 hour, then cooled to room temperature (25°C), to prepare a porous conductive carbon composite material.

Embodiment 3

[0020] 1. Dry 1.5 kg of rice husk and pulverize it into 60-mesh rice husk powder, then add 10 kg of solute mass percentage concentration to 10% hydrofluoric acid solution, stir evenly, place in a hydrothermal reaction kettle, React at a constant temperature of 170°C for 4 hours; filter and wash until the filtrate is neutral, and dry to obtain desiliconized rice husk powder;

[0021] 2. Take 0.2 kg of desiliconized rice husk powder obtained in step 1 and mix it with 0.13 kg of zinc carbonate, and mix the resulting mixture in a tube furnace. The rate was raised to 700° C., kept at this temperature for 2.5 hours, and cooled to room temperature (25° C.) to prepare a porous conductive carbon composite material.

technical field

[0001] The invention belongs to the high-value application field of agricultural solid waste resources, and in particular relates to a preparation method of a rice husk-based porous conductive carbon material. Background technique

[0002] Agricultural solid waste is a kind of natural material with abundant resources on the earth. Straw is a common type of agricultural solid waste. Chinese patent CN 102107864 B discloses a method for preparing biomass conductive carbon. The method uses biomass such as straw as raw materials, and under the action of a catalyst, adopts high-temperature carbonization to prepare a conductive carbon material. However, the conductive carbon material prepared by this method has a narrow pore size distribution, and its application range is limited.

[0003] Rice husk is a common solid waste and a valuable natural resource containing silicon. According to statistics, the annual output of rice husk in my country has reached more th...

Examples

Embodiment 1

[0014] 1. Dry 1 kg of rice husk and pulverize it into 60-mesh rice husk powder, then add 8 kg of solute mass percentage concentration to 10% hydrofluoric acid solution, stir evenly, place in a hydrothermal reaction kettle, React at a constant temperature of 180°C for 5 hours; filter and wash until the filtrate is neutral, and dry to obtain desiliconized rice husk powder;

[0015] 2. Take 0.25 kg of desiliconized rice husk powder and 0.2 kg of zinc carbonate obtained in step 1, mix them evenly, place the resulting mixture in a tube furnace, and put it in a mixed atmosphere of nitrogen and argon (volume ratio: 1:1) Then, the temperature was raised to 800°C at a rate of 15°C / min, kept at this temperature for 3 hours, and then cooled to room temperature (25°C) to prepare a porous conductive carbon composite material.

Embodiment 2

[0017] 1. Dry 0.5 kg of rice husk and pulverize it into 60-mesh rice husk powder, then add 10 kg of solute mass percentage concentration to 5% hydrofluoric acid solution, stir evenly, place in a hydrothermal reaction kettle, React at a constant temperature of 160°C for 2 hours; filter and wash until the filtrate is neutral, and dry to obtain desiliconized rice husk powder;

[0018] 2. Take 0.1 kg of desiliconized rice husk powder and 0.2 kg of zinc carbonate obtained in step 1, mix them evenly, place the resulting mixture in a tube furnace, and raise the temperature at a rate of 10°C / min under a nitrogen atmosphere. to 600°C, and kept at this temperature for 1 hour, then cooled to room temperature (25°C), to prepare a porous conductive carbon composite material.

Embodiment 3

[0020] 1. Dry 1.5 kg of rice husk and pulverize it into 60-mesh rice husk powder, then add 10 kg of solute mass percentage concentration to 10% hydrofluoric acid solution, stir evenly, place in a hydrothermal reaction kettle, React at a constant temperature of 170°C for 4 hours; filter and wash until the filtrate is neutral, and dry to obtain desiliconized rice husk powder;

[0021] 2. Take 0.2 kg of desiliconized rice husk powder obtained in step 1 and mix it with 0.13 kg of zinc carbonate, and mix the resulting mixture in a tube furnace. The rate was raised to 700° C., kept at this temperature for 2.5 hours, and cooled to room temperature (25° C.) to prepare a porous conductive carbon composite material.