Method for preparing nitrogen-doped carbon adsorbents for adsorbing CO2

Abstract

The invention discloses a method for preparing nitrogen-doped carbon adsorbents for adsorbing CO2. The method is characterized by including treating fast-growing poplar bark, nitrogen-containing compounds and pure water under high-temperature and high-pressure hydrothermal conditions and then carrying out centrifuging and separating to obtain dark brown solid products; washing the dark brown solid products by the aid of distilled water and absolute ethyl alcohol by several times until filtrate is clear; drying the filtrate at the temperatures of 80 DEG C and then carrying out calcining at the high temperatures under the protection of nitrogen to obtain the nitrogen-doped carbon adsorbents with developed micropore structures. The fast-growing poplar bark is used as a raw material, the nitrogen-containing compounds are used as nitrogen sources, and the pure water is used as a solvent. The method has the main advantages that the nitrogen-doped carbon adsorbents are high in gaseous CO2 adsorption capacity; the bark which is forestry waste is used as the raw material, is environmentally friendly, is low in cost and is easily available, the water is used as the solvent, the nitrogen-containing compounds are used as the nitrogen sources, calcining is carried out at the high temperatures under the protection of inert gas, accordingly, the nitrogen-doped carbon adsorbents with large specific surface areas and the developed micropore structures can be obtained, and the method is favorable for CO2 gas adsorption effects; hydrothermal preparation conditions, doping ratios of the nitrogen sources and high-temperature carbonization parameters can be regulated and controlled, accordingly, the surface functional group composition and the pore size distribution of the prepared nitrogen-doped carbon adsorbents can be controlled, and the nitrogen-doped carbon adsorbents with the excellent adsorption performance can be obtained; hydrothermal reaction operation procedures are simple, the method is low in cost, the micropore structures are developed and are controllable, and excellent adsorption effects can be realized.

Description

[0001] Technical field: [0002] The invention relates to the field of preparation of nanomaterials, in particular to a method for absorbing CO 2 Preparation method of nitrogen-doped carbon adsorbent [0003] Background technique: [0004] CO 2 , N 2 O and CH 4 It is the main harmful gas that affects the greenhouse effect. However, in recent years, the emission of these gases has increased day by day, which will cause obvious climate changes, including global temperature rise, sea level rise, and El Niño phenomenon. CO from fossil fuel combustion 2 is the main harmful gas, accounting for 50%, until a suitable renewable alternative energy source is found, the CO 2 Effective capture of the gas is necessary to reduce emissions. Commonly used effective CO 2 Capture methods include chemical adsorption, strong alkali neutralization, low-temperature storage, etc., but the high cost of equipment and chemical reagents used, non-renewable or even toxic, etc. limit the practical ap...

AI Technical Summary

Problems solved by technology

The absorbent has a relatively stable reaction activity and is an ideal absorbent for the hydrogen production reaction process of natural gas reforming. However, the reaction is carried out in multiple steps, and all involve high temperature activation, which is not easy to control and the temperature has a great influence on the performance of the product.

[0011] In summary, the currently produced CO 2 Adsorbents mainly use polymers, coal powder, metal salts, zeolites, etc. as raw materials, and organic solvents as reagents. After acid-base treatment, high-temperature or several-step complex treatment processes are used to obtain porous or rich CO2-rich adsorbents. 2 Adsorbents with combined functional groups. These methods usually require multi-step reactions. The reaction conditions have a great impact on the adsorption performance of the product, which increases the cost of the reaction and is not conducive to large-scale development, production and utilization.

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