High Gravity-Enhanced Direct Air Capture: A Leap Forward in CO<sub>2</sub> Adsorption Technology

Given the global pressure of climate change and ecological equilibrium, there is an urgent need to develop effective carbon dioxide (CO<sub>2</sub>) capture technology. Due to its comprehensiveness and flexibility, Direct Air Capture (DAC) technology has emerged as a vital supplement to...

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Bibliographic Details
Main Authors: Shufei Wang, Youzhi Liu, Chengqian Zhang, Shuwei Guo, Yuliang Li
Format: Article
Language:English
Published: MDPI AG 2024-02-01
Series:Atmosphere
Subjects:
Online Access:https://www.mdpi.com/2073-4433/15/2/238
Description
Summary:Given the global pressure of climate change and ecological equilibrium, there is an urgent need to develop effective carbon dioxide (CO<sub>2</sub>) capture technology. Due to its comprehensiveness and flexibility, Direct Air Capture (DAC) technology has emerged as a vital supplement to traditional emission reduction methods. This study aims to innovate Direct Air Capture (DAC) technology by utilizing the ultrasonic impregnation method to load Tetraethylenepentamine (TEPA) onto alumina (Al<sub>2</sub>O<sub>3</sub>) as the adsorbent. Furthermore, high gravity adsorption technology is integrated to significantly enhance the efficiency of DAC. Characterization tests, including BET, FTIR, TG, XRD, and SEM-EDS, confirm the structural stability and high capture capacity of the adsorbent. Additionally, this study demonstrates the rapid and efficient capture of CO<sub>2</sub> from the air using TEPA-Al<sub>2</sub>O<sub>3</sub> adsorbent under high gravity conditions for the first time. Under optimal conditions with TEPA loading at 15.06%, a high gravity factor of 2.67, and a gas flow rate of 30 L/min, TEPA-Al<sub>2</sub>O<sub>3</sub> achieves a CO<sub>2</sub> adsorption capacity of 48.5 mg/g in RAB, which is an improvement of 15.56 mg/g compared to traditional fixed-bed technology. Moreover, it reaches adsorption saturation faster under high gravity conditions, exhibiting a significantly higher adsorption rate compared to traditional fixed-bed systems. Furthermore, the adsorption process better conforms to the Avrami model. Steam stripping regeneration is utilized to regenerate the adsorbent, demonstrating excellent regeneration performance and stable adsorption capacity, thereby proving its feasibility and economic benefits as a DAC technology.
ISSN:2073-4433