Nitrogen-enriched active biomass coke and preparation method thereof

Abstract

The invention discloses a preparation method of nitrogen-enriched active biomass coke. The preparation method comprises the following steps: (1) carbonizing a biomass raw material in a pyrolysis furnace with a nitrogen atmosphere, heating to 400-600 DEG C, and maintaining the final temperature for 30-60 minutes to preliminarily obtain a carbonized biomass coke of the raw material; (2) heating the carbonized biomass coke to 700-900 DEG C in an inert gas atmosphere, and switching the inert gas atmosphere in the furnace into a water vapor atmosphere when a set temperature is reached, and staying at the temperature for 30-60 minutes; and (3) switching the water vapor atmosphere into a NH3 atmosphere, putting the product obtained after the treatment in the step (2) into the NH3 atmosphere at 700-900 DEG C to perform ammoniated surface chemical treatment, staying for 60-100 minutes, and cooling to room temperature in an inert protection atmosphere to obtain the nitrogen-enriched active biomass coke. The invention also discloses a product prepared by the method. The product prepared by the method disclosed by the invention has a good pore structure obtained by activation and a lot of surface alkaline nitrogen-containing functional groups obtained by ammoniation, can well realize effective adsorption of acid gasses of CO2, SO2 and NOx at a high temperature.

Description

technical field [0001] The invention belongs to the field of biomass preparation and application, and in particular relates to a nitrogen-enriched active biomass coke and a preparation method thereof, which is suitable for CO in flue gas discharged from coal-fired power plants and the like. 2 of adsorption. Background technique [0002] CO 2 It is the main gas that causes the greenhouse effect, accounting for about 65-70% of the total amount of greenhouse gases. Global warming is already the biggest environmental problem that the world has to face today. my country's current CO 2 The total annual emissions have reached 6 billion tons, ranking first in the world, and are facing enormous international pressure. However, my country's coal-based energy structure is difficult to change for a long time, and coal-fired power plants have always been my country's CO2 2 The most important source of emissions, the CO 2 Emissions account for about 1 / 3 of similar emission sources in...

AI Technical Summary

Problems solved by technology

[0005] However, the above-mentioned preparation of nitrogen-doped porous carbon materials has the following problems, which make the process conditions demanding and complex, and the adsorption performance of the prepared product under high temperature conditions still has the defect of low efficiency:

[0006] (1) The hydrothermal method is adopted. Although the temperature requirement is not high, it needs to be carried out in a relatively high pressure vessel. It is a test for the equipment's pressure resistance and internal corrosion resistance. The technology is difficult and the safety is relatively poor, so it is not suitable for large-scale scale production

[0007] (2) In the technical solution disclosed above, since the hydrothermal carbonization reaction and the subsequent removal process of the stencil agent require a long reaction time, and the cooling of the motor requires a large amount of water, the process is more complicated and consumes more energy. energy

[0008] (3) Using biomass derivatives (glucose, β-cyclodextrin, etc.) as a carbon source and nitrogen-containing polymers as a nitrogen source to prepare nitrogen-doped porous carbon materials will increase the cost invisibly in the selection of raw materials

[0009] (4) The adsorption efficiency and selective adsorption value of specific target adsorbates of the prepared nitrogen-doped porous carbon materials at high temperature are still relatively low, which is not conducive to large-scale engineering applications

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