Adsorption performance of amine-functionalized red mud-based adsorbent for CO₂ capture.

Area of Science:

• Materials Science
• Environmental Science
• Chemical Engineering

Background:

• Industrial solid waste, such as red mud, presents significant disposal challenges.
• Efficient carbon dioxide (CO2) capture technologies are crucial for mitigating climate change.
• Resource utilization of industrial byproducts can lead to sustainable solutions.

Purpose of the Study:

• To develop a novel solid amine adsorbent from red mud for efficient CO2 capture.
• To investigate the impact of organic amine type and loading on adsorption performance.
• To evaluate the cyclic stability and adsorption mechanisms of the developed adsorbent.

Main Methods:

• Red mud processing and functionalization with organic amines.
• Characterization using nitrogen adsorption-desorption, XRD, TGA, and SEM.
• CO2 adsorption-desorption tests and kinetic analysis.
• Cyclic stability testing over multiple adsorption-desorption cycles.

Main Results:

• Successfully prepared a red mud-based solid amine adsorbent with enhanced CO2 capture capacity.
• Identified MRM-20-TETA as the optimal adsorbent, achieving 23.94 mg/g CO2 adsorption, a 29-fold increase over pristine red mud.
• Demonstrated good cyclic stability with only a 9.9% capacity decrease after five cycles.
• Kinetic analysis indicated a combined physical and chemical adsorption mechanism.

Conclusions:

• Red mud can be effectively utilized as a precursor for developing high-performance CO2 adsorbents.
• The developed amine-functionalized red mud adsorbent offers a promising, stable, and cost-effective solution for CO2 capture.
• This research provides valuable insights into waste valorization and sustainable carbon capture strategies.