Lignin-Based Porous Supraparticles for Carbon Capture.

Area of Science:

• Materials Science
• Carbon Materials
• Nanotechnology

Background:

• Existing nanoparticle systems for CO2 capture face limitations in mass transport and kinetics.
• Development of advanced porous carbon materials is crucial for effective carbon capture technologies.

Purpose of the Study:

• To synthesize and characterize multiscale carbon supraparticles (SPs) using lignin and cellulose nanofibrils (CNFs).
• To evaluate the CO2 capture performance and suitability for regeneration of these novel carbon SPs.

Main Methods:

• Soft-templating of lignin nano- and microbeads with CNFs to form precursor constructs.
• Oxidative thermostabilization followed by controlled carbonization to yield carbon SPs.
• Characterization of mechanical strength, surface area, and CO2 adsorption capacity.

Main Results:

• Synthesized carbon SPs exhibit high mechanical strength (58 N·mm⁻³) and surface area (1152 m²·g⁻¹).
• Achieved significant CO2 capture capacity (77 mg CO₂·g⁻¹) with low pressure drop (∼33 kPa·m⁻¹).
• Demonstrated effective CO2 uptake without heteroatom doping and successful regeneration over multiple cycles.

Conclusions:

• Lignin-derived carbon SPs offer hierarchical pore structures advantageous for CO2 capture.
• These materials address mass transport and kinetic limitations of nanoparticle-based adsorbents.
• The developed porous SP carbon systems present a low-cost, high-activity solution for gas sorption and CO2 capture.