Chemical and Physical Ionic Liquids in CO₂ Capture System Using Membrane Vacuum Regeneration

Area of Science:

• Chemical Engineering
• Environmental Science
• Materials Science

Background:

• Achieving net-zero CO2 emissions necessitates advanced Carbon Capture Utilization and Storage (CCUS) technologies.
• Developing sustainable and cost-effective separation technologies is crucial for CCUS implementation.

Purpose of the Study:

• To present a novel CO2 capture strategy combining non-dispersive absorption with membrane vacuum regeneration (MVR).
• To evaluate the performance of two imidazolium ionic liquids, [emim][Ac] and [emim][MS], in this MVR system.

Main Methods:

• Continuous absorption-desorption experiments were conducted using polypropylene hollow fiber membrane contactors.
• Two specific ionic liquids, [emim][Ac] and [emim][MS], were tested for CO2 absorption and desorption characteristics.
• Membrane vacuum regeneration (MVR) performance was assessed at 313 K and 0.04 bar vacuum pressure.

Main Results:

• [emim][Ac] demonstrated superior desorption behavior, achieving 92% MVR performance efficiency.
• [emim][MS] reached 83% efficiency under identical conditions.
• MVR technology enhanced overall CO2 capture performance by up to 61% for [emim][Ac] and 21% for [emim][MS].

Conclusions:

• The study highlights the potential of MVR technology with chemical ionic liquids for efficient CO2 capture.
• Further techno-economic assessments are required to validate the large-scale application feasibility of this CO2 desorption approach.