Anti-degradation Biphasic Absorbent for Efficient and Stable CO₂ Capture

Area of Science:

• Chemical Engineering
• Environmental Science
• Materials Science

Background:

• Amine degradation limits scalability of CO2 capture using biphasic absorbents.
• High chemical stability is crucial for efficient industrial CO2 separation.

Purpose of the Study:

• To develop a highly stable biphasic absorbent for CO2 capture with low regeneration energy.
• To overcome the challenge of amine degradation in industrial CO2 absorption processes.

Main Methods:

• Screening of amine compounds based on molecular structure for high stability.
• Preparation and evaluation of a novel biphasic absorbent: 3-amino-1-propanol (MPA)-2-amino-2-methyl-1-propanol (AMP)-N,N,N',N'-tetramethyl-1,3-propanediamine (TMPDA)-polyethylene glycol dimethyl ether (NHD).
• Comprehensive characterization of absorbent performance, stability, and degradation mechanisms.

Main Results:

• The MPA-AMP-TMPDA-NHD absorbent demonstrated effective phase separation, low regeneration energy (1.99 GJ/t-CO2, 48.3% reduction vs. MEA), and high stability.
• CO2-rich phase loading reached 4.13 mol/L with a 53.1% volume fraction.
• Degradation testing showed minimal alkalinity loss (0.29 mol/kg thermal, ~10% oxidative) and reduced NH3 emissions compared to MEA-NHD.

Conclusions:

• The developed biphasic absorbent offers a promising solution for low-energy, stable CO2 capture in industrial applications.
• This study provides a theoretical basis for designing advanced absorbents resistant to degradation.
• The findings pave the way for more scalable and efficient chemical absorption methods for CO2 mitigation.