CN-121974329-A - Biomass-based ultra-microporous carbon material and preparation method and application thereof

Abstract

The invention discloses a biomass-based ultra-microporous carbon material, and a preparation method and application thereof. The biomass-based ultra-microporous carbon material with the average pore diameter smaller than 1 nm is prepared by taking a large amount of agriculture and forestry waste biomass bamboo shoot shells as a raw material, crushing the raw material, and performing pretreatment and pore-forming steps. The invention not only realizes the value-added utilization of large amount of agricultural and forestry abandoned biomass bamboo shoot shells, but also the prepared bamboo shoot shell-based ultra-microporous carbon material has high-efficiency adsorption capacity on heavy metal ion hexavalent chromium in water, the maximum adsorption capacity reaches 500 mg/g, and the bamboo shoot shell-based ultra-microporous carbon material can be used as a high-efficiency adsorbent for adsorbing and removing heavy metal ion hexavalent chromium in water.

Inventors

• HU HUI
• ZHANG WEIQUAN

Assignees

• 福州大学

Dates

Publication Date

20260505

Application Date

20260305

Claims (8)

1. 1. The preparation method of the biomass-based ultra-microporous carbon material is characterized by comprising the following steps of: S1, crushing biomass bamboo shoot shells to prepare biomass particles; S2, uniformly mixing the biomass particles prepared in the step S1 with water according to a solid-to-liquid ratio, adding the mixture into a reaction kettle, performing hydrothermal reaction, cooling to room temperature, separating a solid product, and washing and drying to prepare biomass hydrothermal carbon; S3, taking the biomass hydrothermal carbon prepared in the step S2, adding a pore-forming agent potassium hydroxide, pyrolyzing under an inert atmosphere, cooling to room temperature after the reaction is finished, taking out, washing and drying to prepare the biomass-based ultra-microporous carbon material.
2. 2. The preparation method of the biomass-based ultra-microporous carbon material according to claim 1, wherein the solid-to-liquid ratio of biomass particles to water in the step S2 is 1 g (1-100) mL.
3. 3. The preparation method of the biomass-based ultra-microporous carbon material according to claim 1, wherein the hydrothermal reaction temperature in the step S2 is 100-300 ℃ and the hydrothermal reaction time is 1-20 h.
4. 4. The preparation method of the biomass-based ultra-microporous carbon material according to claim 1, wherein the mass ratio of biomass hydrothermal carbon to potassium hydroxide in the step S3 is 1 g (0.1-20) g.
5. 5. The preparation method of the biomass-based ultra-microporous carbon material according to claim 1, wherein the inert atmosphere in the step S3 is nitrogen, and the gas flow rate is 40-60 mL/min.
6. 6. The preparation method of the biomass-based ultra-microporous carbon material according to claim 1, wherein the pyrolysis temperature in the step S3 is 500-1000 ℃ and the pyrolysis time is 0.5-5 h.
7. 7. A biomass-based ultra-microporous carbon material prepared by the preparation method of any one of claims 1-6.
8. 8. Use of the biomass-based ultra-microporous carbon material according to claim 7 for adsorbing hexavalent chromium which is heavy metal ions in water.

Description

Biomass-based ultra-microporous carbon material and preparation method and application thereof Technical Field The invention belongs to the technical field of preparation of heavy metal adsorption materials, and particularly relates to a biomass-based ultra-microporous carbon material, and a preparation method and application thereof. Background The hexavalent chromium of heavy metal ions is one of typical heavy metal ion pollutants in industrial wastewater of electroplating, leather tanning, wood preservation, dye production and the like. It constitutes a serious threat to the ecosystem and human health. It is difficult to biodegrade in the environment, is easy to be absorbed by the root of crops and causes diseases, and can kill aquatic organisms such as fish and the like under low concentration. The hexavalent chromium of heavy metal ions can also cause serious injury to the respiratory system, digestive system and liver and kidney functions of human bodies, and even cause death. In view of their high toxicity, bioaccumulation and migration, chromium-containing wastewater must be effectively treated prior to discharge. The adsorption method is widely applied to the treatment of the hexavalent chromium of the heavy metal ions in the industrial wastewater due to simple operation and high separation efficiency. The adsorbent is one of key technologies for realizing an adsorption method, and the commercial microporous activated carbon has been widely applied to the field of separation of hexavalent chromium of heavy metals. The ultra-microporous carbon material is a porous material with the average pore diameter smaller than 1 nm, has the advantages of stable chemical structure, large specific surface area, high porosity and the like, and has excellent adsorption performance on metal ions. The current biomass ultra-microporous carbon material is prepared by taking high-value substances such as glucose, chitosan and the like as raw materials. Bamboo shoot shells are a large amount of agricultural and forestry waste biomass, and are usually directly discarded, buried or burnt, so that not only is the resource wasted, but also serious environmental pollution is caused. Based on the concept of treating waste with waste and recycling economy, the invention uses waste biomass bamboo shoot shells as raw materials to convert the waste biomass bamboo shoot shells into biomass-based ultra-microporous carbon materials. The material is specially used for adsorbing hexavalent chromium in industrial wastewater, thereby not only realizing high-value utilization of waste resources, but also providing a new economic and environment-friendly way for treating the chromium-containing wastewater. In the prior art, the invention patent CN107626280A discloses a method for preparing a charcoal-based heavy metal adsorbent by taking potassium phosphate as an activator, but mainly aims at cadmium ion adsorption, the pore size distribution of the obtained material is wider, the adsorption effect on other heavy metal ions is not reflected, the invention patent CN102895957A discloses a method for preparing a Fe 2O3/Fe3O4 composite adsorbent by taking moso bamboo as a template, although biomass resources are utilized, the preparation process is complex, multi-step chemical treatment is involved, and the adsorption performance of a final product still has room for improvement. Therefore, a new material and a new technology which take waste biomass as a raw material, have green process, can directionally construct a super-microporous structure and realize the efficient selective adsorption of chromium ions are developed, and have important scientific value and application prospect. Disclosure of Invention The invention aims to overcome the defects of the prior art, provides a biomass-based ultra-microporous carbon material, a preparation method and application thereof, and a method for preparing the carbon material with a uniform ultra-microporous structure through a controllable green process, and proves that the material has excellent selective adsorption performance and high adsorption capacity on hexavalent chromium ions in water. In order to achieve the above purpose, the invention adopts the following technical scheme: The invention aims at providing a preparation method of a biomass-based ultra-microporous carbon material, which comprises the following steps: S1, crushing biomass bamboo shoot shells to prepare biomass particles; S2, uniformly mixing the biomass particles prepared in the step S1 with water according to a solid-to-liquid ratio, adding the mixture into a reaction kettle, performing hydrothermal reaction, cooling to room temperature, separating a solid product, and washing and drying to prepare biomass hydrothermal carbon; S3, taking the biomass hydrothermal carbon prepared in the step S2, adding a pore-forming agent potassium hydroxide, pyrolyzing under an inert atmosphere, cooling to room temperature after the reaction