CN-118217941-B - Solid-liquid composite adsorbent for capturing carbon dioxide and preparation method and application thereof

CN118217941BCN 118217941 BCN118217941 BCN 118217941BCN-118217941-B

Abstract

The application provides a solid-liquid composite adsorbent for carbon dioxide trapping, a preparation method and application thereof, and particularly relates to the technical field of carbon dioxide trapping materials. The solid-liquid composite adsorbent comprises a shell and an inner core, wherein the shell comprises hydrophobic SiO 2 and hydrophobic modified biochar, and the inner core is acid gas absorption liquid. The application combines the high specific surface area, low corrosiveness of the solid adsorbent and the high adsorption capacity and high selectivity of the acid gas absorption liquid by utilizing the unique solid-packed liquid structure, improves the adsorption capacity of the adsorbent, and wraps the inner core of the acid gas absorption liquid by utilizing the hydrophobic solid particle shell, thereby reducing the contact area between the acid gas absorption liquid and the trapping equipment and avoiding the corrosion of the acid gas absorption liquid to the equipment. According to the embodiment, the adsorption capacity of the solid-liquid composite adsorbent provided by the application to CO 2 is 1.5-5 mmol/g.

Inventors

JI RENJING
YU XIAORONG
PENG KAINAN
CUI JINGYI
Wang Benru
FAN ZHENGYANG
YANG HUAN
SU GAOSHEN

Assignees

长江大学

Dates

Publication Date: 20260505
Application Date: 20240426

Claims (4)

1. The preparation method of the solid-liquid composite adsorbent comprises a shell and an inner core, wherein the shell comprises hydrophobic SiO 2 and hydrophobic modified biochar, and the inner core is acid gas absorption liquid; the content of the hydrophobic SiO 2 in the shell is more than or equal to 80wt% and less than 100wt%, the content of the hydrophobic modified biochar is more than 0 and less than or equal to 20wt%, the particle size of the hydrophobic SiO 2 is 3-15 nm, and the particle size of the hydrophobic modified biochar is 10-23 mu m; The volume ratio of the mass of the shell to the volume of the inner core is 1 g:8-12 mL; the particle size of the solid-liquid composite adsorbent is 40-60 mu m; The acid gas absorption liquid comprises an alkaline absorption liquid; The alkaline absorption liquid comprises one or more of K 2 CO 3 solution, organic amine and ammonia water solution; The preparation method of the solid-liquid composite adsorbent is characterized by comprising the following steps: stirring and mixing the hydrophobic SiO 2 , the hydrophobic modified biochar and the acid gas absorption liquid to obtain a solid-liquid composite adsorbent; The rotation speed of stirring and mixing is 8000-15000 r/min.
2. The preparation method of claim 1, wherein the stirring and mixing time is 120-180 s.
3. The preparation method according to claim 1, wherein the hydrophobically modified biochar is a silane coupling agent modified biochar, the preparation method comprising the steps of: mixing biochar with alkali solution, and activating to obtain activated biochar; And mixing the activated biochar, the silane coupling agent and the alcohol solvent, and performing heating modification to obtain the hydrophobically modified biochar.
4. The application of the solid-liquid composite adsorbent prepared by the preparation method of any one of claims 1-3 in capturing carbon dioxide.

Description

Solid-liquid composite adsorbent for capturing carbon dioxide and preparation method and application thereof Technical Field The invention belongs to the technical field of carbon dioxide trapping materials, and particularly relates to a solid-liquid composite adsorbent for carbon dioxide trapping, and a preparation method and application thereof. Background The CO 2 capturing material refers to a material capable of adsorbing and storing CO 2, is mainly applied to the fields of CO 2 capturing, gas separation, storage and the like, and can be divided into a liquid absorbent and a solid absorbent. Common liquid absorbents comprise organic amine, ammonia water solution, ionic liquid and the like, carbon trapping is carried out by utilizing solution absorption, the trapping efficiency is relatively high, the adaptability to flue gas is good, but the regeneration energy consumption of a solvent in the trapping process is high, the thermal stability is poor, and certain corrosiveness is brought to equipment. The solid adsorbent is more resistant to the high temperature of the flue gas, has good chemical stability, low toxicity, low corrosiveness and low cost, but has no competitive advantage in adsorption capacity and is easy to be inactivated by the influence of water vapor in the flue gas. Aiming at the problems of the liquid absorbent and the solid absorbent, a solid-liquid composite absorbent is provided, most of the existing solid-liquid composite absorbent is solid supported amine absorbent materials, and the solid-liquid composite absorbent is prepared by using an adhesive, a cross-linking agent, a template agent and the like through subsequent heat treatment, has long preparation period and expensive raw materials, and simultaneously generates a large amount of toxic and harmful gases and liquid. Disclosure of Invention In view of the above, the present invention aims to provide a solid-liquid composite adsorbent for capturing carbon dioxide. The solid-liquid composite adsorbent provided by the invention has the advantages of large adsorption capacity for CO 2, high adsorption rate, low corrosiveness for equipment, simple manufacturing method and environment friendliness. In order to solve the technical problems, the invention provides the following technical scheme: The invention provides a solid-package liquid composite adsorbent, which comprises a shell and an inner core; the shell comprises hydrophobic SiO 2 and hydrophobic modified biochar; the inner core is acid gas absorption liquid. Preferably, the content of the hydrophobic SiO 2 in the shell is more than or equal to 80wt% and less than 100wt%, and the content of the hydrophobic modified biochar is more than 0 and less than or equal to 20wt%; The particle size of the hydrophobic SiO 2 is 3-15 nm, and the particle size of the hydrophobic modified biochar is 10-23 mu m. Preferably, the volume ratio of the mass of the shell to the volume of the inner core is 1 g:8-12 mL. Preferably, the particle size of the solid-liquid composite adsorbent is 40-60 μm. Preferably, the acid gas absorption liquid comprises an alkaline absorption liquid. Preferably, the alkaline absorption liquid comprises one or more of a K 2CO3 solution, an organic amine, and an aqueous ammonia solution. The invention also provides a preparation method of the solid-liquid composite adsorbent, which comprises the following steps: stirring and mixing the hydrophobic SiO 2, the hydrophobic modified biochar and the acid gas absorption liquid to obtain a solid-liquid composite adsorbent; The rotation speed of stirring and mixing is 8000-15000 r/min. Preferably, the stirring and mixing time is 120-180 s. Preferably, the hydrophobic modified biochar is silane coupling agent modified biochar, and the preparation method comprises the following steps: mixing biochar with alkali solution, and activating to obtain activated biochar; And mixing the activated biochar, the silane coupling agent and the alcohol solvent, and performing heating modification to obtain the hydrophobically modified biochar. The invention also provides application of the solid-liquid composite adsorbent prepared by the preparation method in capturing carbon dioxide. The application provides a solid-liquid composite adsorbent for capturing carbon dioxide, which comprises a shell and an inner core, wherein the shell comprises hydrophobic SiO 2 and hydrophobic modified biochar, and the inner core is acid gas absorption liquid. The application combines the high specific surface area, low corrosiveness of the solid adsorbent and the high adsorption capacity and high selectivity of the acid gas absorption liquid by utilizing a unique solid-packed liquid structure, improves the adsorption capacity of the adsorbent, wraps the inner core of the acid gas absorption liquid by utilizing the hydrophobic solid particle shell, reduces the contact area between the acid gas absorption liquid and the trapping equipment, avoids the corrosi